I've complained before that Americans eat way too much meat. I'm not saying we should all run out and become vegetarians, mind you, but if we all had to hunt down, kill and butcher our own meals, I'm pretty sure most people's diets would migrate away from so many burgers and towards more broccoli, asparagus, apples and tofu. I know mine would.

And if we ate a healthier mix, our agricultural land could feed more people since, as I've said before, it takes several pounds of grain crops, and therefore more acreage, to produce one pound of meat. While we're at it, the reduction in the required number of methane belching cows would mean, among other things, a reduction in the number of cow farts wafting up into the atmosphere, contributing to global warming.

Let's be honest, though: As long as juicy burgers are available at drive-through windows and slabs of beef come conveniently wrapped in Styrofoam and cellophane at the local market, changing people's eating habits enough to make a difference is a tough sell. So if, for the foreseeable future, cow farts remain a smelly fact of life, it'd be nice if we could at least put 'em to good use.

Yesterday, the EPA took a big step towards making that happen by releasing guidelines that can "help farmers manage livestock waste and boost farm earnings while reducing greenhouse gases." While the idea of converting livestock manure into biofuel isn't new, the EPA's guidelines should encourage more farmers to see manure as a secondary source of income, rather than merely something that needs to be disposed of.

The idea is as compelling as it is simple: Manure emits methane, which is among the most noxious of greenhouse gasses. Capture it and you cut down on climate change. So far, the EPA's voluntary methane capture program has been successful: In 2001, total U.S. methane emissions were 5% below emissions in 1990.

The new guidance helps take things a step further by helping farmers process manure into useful biogas. The biogas can then be used to produce electricity for the farm, or can be sold to a local utility company, providing farmers with an additional income stream.

More information on the "Methane to Markets" initiative can be found on the EPA's Website.

Congress is pushing hard for expanding the use of renewable fuels and electric motors as if they are the panacea for creating a more sustainable nation, but what of improving our rail system?

According to the U.S. Department of Energy, trains are more energy efficient than traveling by car, bus, or plane.

2003 data showing BTUs (British Thermal Units) of energy consumed per passenger mile

2,717 Light rail 3,374 Amtrak 3,549 Passenger vehicles: 3,587 Air carriers

If we fill the seats of trains more consistently, then they become even more efficient. The amount of research dollars invested in improving train engines is probably a fraction of what is spent on autos, so I bet there is a higher ceiling for improving trains even more. Despite this superior efficiency, we in the U.S. have done almost nothing to support train travel. It is time for a national policy develop regional train systems so that they can serve commuters, sustainability, and business most effectively. The federal government subsidizes ethanol and hybrid vehicles to encourage energy efficiency, and trains deserve equal support.

The most significant drawbacks to train travel can be the price and time involved compared to the freedom of driving a car . But if we could somehow compensate the train lines for all of the emissions that aren't going into the air because of the cars that they replace, then a train ticket would become a relative bargain.

We have local taxes to support mass transportation, but does that factor into trains that cross state lines? Imagine the greenhouse gases saved if everyone who needed to get from New York to Boston or Portland to Seattle went by rail.

The time problem could be fixed partially by having more express trains and reducing the number of trains that stop every 5 minutes. Why stop a train for hundreds of riders for the one or two people that get off at a stop? Passenger who use low volume stops might have to wait longer for a train or take the bus, but they would still have access to public transit if we optimized the schedules for the greatest number of passengers. It is ridiculous that in some areas it takes twice as long to get somewhere by train as it does by car.

We could take a page from the European book on this and install more of the faster modern trains, especially in high population areas (such as the Northeast corridor or San Francisco to Sacramento).

I was prompted to write about trains and energy efficiency after reading about a new oxidation catalyst that substantially reduces the emissions from diesel trains. The technology is being tested by Union Pacific, and initial tests show it can reduce particulate emissions by 50 percent, unburned hydrocarbons by 38 percent, and carbon monoxide by 82 percent. Wow. If trains didn't smell bad, would more people ride them? Maybe.

I took the train from Philadelphia to New York hundreds of times, and despite the odor, it was the cheapest and most convenient way to get between cities. I'm amazed that so many people fly between those cities because the time involved in security and deplaning makes a direct train trip a faster commute.

Reducing emissions and the cost of transportation is a national issue, and the federal government should coordinate the regional efforts. Let's identify the best routes for getting the most cars off the highway, and the most cost-efficient way of doing so. We can blame Amtrak but the opportunity is bigger than they are and should be met on a national level. If it can be made cost effective to transport riders across country borders in Europe, we should be able to do it here. However, one of the mitigating factors is the price of fuel, which is much higher in Europe than here, but that's an entirely different discussion.

Train ridership is up in Chicago, and other areas, which is an encouraging development. Trains also sustain us by allowing us to relax or be productive as needed. Read a book, talk to a stranger, nap, look out the window, or go online with a free WiFi connection, and you'll be much better off than dealing with road rage and toll booths.

Americans have the nasty habit of identifying with their careers at the expense of everything else. The first thing most of us ask each other when we meet is "what do you DO?" And how sad is it that our jobs are considered the best measure of who we really are? What we do "for a living" should be the thing that supports us and allows us to live our own versions of a rich, full life.

I prefer the European approach. Once long ago, while sharing tapas and wine with friends in Barcelona, I made the mistake of asking one person at the table what another – a lifelong friend of the first who'd walked into the bar late and wearing a suit – did for a living.

"I don't have a clue," she said. "Something to do with money, I think."

Perfect. Because what most of us do from nine to five we do for someone else.

It's how you spend the rest of your time that really defines you: Do you spend it dancing with friends? Alone in a studio, spattered with paint? Climbing mountains? What are you passionate about? If you're an American, bombarded by sophisticated advertising that steers and shapes you, temps you to buy, buy, buy with promises of happiness and freedom, do you even know anymore?

There is, of course, one more option: To be one of the lucky ones who blend their passions and their professions so seamlessly that it's impossible to distinguish between "work" and "fun." That's the Holy Grail, that's when life really Matters.

Most of us, right this minute, are probably not lucky enough to have found that opportunity to make a living from the things we love. But all of us can at least make sure we give some of our free time to taking care of the things in this world we count on to take care of us.

It's that old saw that giving is so much better than receiving: If you love hiking or mountain biking, why not volunteer for the group that maintains your favorite trails? If sailing in the tropics is your thing, protecting the Caribbean's mangrove trees or Australia's coral reefs could be the adventure of a lifetime, one that opens the doors into other cultures wider than they'd be for mere tourists. You'd probably meet some incredible, worthwhile people while you're at it, too.

If you're an artist or musician, why not give a little of your time by sharing your passion with children, the elderly or disabled? If you have more time and a larger sense of adventure, you might find opportunities to share your gifts with people around the world at Escape Artist. You may quickly find that, in doing so, you can get closer than you'd ever dreamed to that holy grail of doing what you love for a living, and living a life that Matters.

During next week's State of the Union address, President Bush is likely to ask for rapidly increasing use of ethanol in the coming decades, according to Reuters. This would be a significant shift from the administration's current strategy of asking for only increases in renewable fuels that the industry is likely to meet anyway.

Is politics at play? Reuters says the White House could ask for a higher volume of ethanol be consumed than democrats are asking for in a proposed bill, 60 billion gallons by 2030. This would steal some thunder from democrats as both parties are fully on the ethanol bandwagon.

But to make this goal achievable, we need more money for cellulosic ethanol research and incentives to build out the infrastructure. As we know, ethanol from corn won't get us there.

Last year's energy budget called for $150 million in biomass related research money, a fraction of what we are spending on fossil fuel and nuclear research. If Bush doesn't combine federal dollars with a sustainable goal, then it will be another empty promise, just like his "replacing our foreign oil imports" words of last year.

Municipalities are passing tougher green building laws to promote sustainable construction, but incentives are more appropriate than passing stringent building codes.

In Washington D.C., the Council has proposed legislation that would apply to all commercial development of greater than 50,000 square feet. While this is admirable, it may scare off developers in some of the poorer neighborhoods who may not want to invest the higher upfront costs for environmental technology in places where rents are lower.

Seattle, on the other hand, appears to be focusing more on incentives (via Sustainablog instead of regulations, and I'm more in favor of that approach.

While there should be minimum building codes that upgrade the current requirements for water recycling, insulation, and energy efficiency, aiming too high can curb investment. Providing strong tax incentives -- faster depreciation, tax credits for installing windows or walls that keep in the heat -- and using the government's buying power (only renting in LEED buildings) is a more market-friendly approach.

In Chicago, Baum Development is planning an uber green office building that will cater to sustainable businesses. The Green Exchange is a four-story 250,000 square foot building that will include "an organic restaurant, an alternative automobile showroom, a sustainable furniture store, a green building supply company, an eco-friendly printer, an environmentally-friendly clothing company, a car sharing service, a bike shop and more."

Wow, an eco-services building in downtown Chicago! Hopefully they will find enough tenants so that people can browse a number of stores to see the many aspects of incorporating sustainability.

There are many ways to Matter in this life, not all of them necessarily involve alternative energy and sustainability. While Matter Magazine focuses mostly on those topics, I believe it's also our duty to highlight interesting, challenging and inspiring information and experiences that fit into the broader context of our mission, which is to explore and celebrate ways to enrich your world while reducing your impact.

So today, I'll turn you all on to the adventures of a very close friend of mine, David Ferris, who right this second is seeking meaning and richness in his life by scaling South America's Mount Aconcagua which, at 22,841 feet is the highest spot of land in the Western Hemisphere. Of course, not everyone will get the connection between risking your life and enriching it, but Dave does. I know because we used to do this sort of stuff together, back before my life migrated more towards changing diapers and mowing organically fertilized lawn and seeking my outdoor adventures in three-hour snippets on a bike or skis. In fact, one of Dave's climbing partners, Terri Schneider was the coach/trainer of our rag-tag expedition racing team.

So if you want a chance at some vicarious armchair adventure, check out Dave's audio posts over the next few weeks as he explores new cultures, tests new limits and scales new heights.

While you're at it, send some good thoughts his way.