Patrick Lyons stands in the middle of a Dumpster, staring at a can of meat.

"I don't know who eats this stuff," he says.

He chucks the can aside and keeps on digging. His ball cap is slung low over his face; it connects to his long, thick, brown sideburns.

He digs down and -- jackpot -- he's found what he's looking for. He holds three small potatoes and a yellow bell pepper up in the air.

He's one step closer to a complete meal.

He places his bounty in a cardboard box and keeps foraging.

"One time a lady walked up to me and offered me $5," he says. "I told her, 'I'm not homeless. This is political.' "

Lyons is a freegan. He doesn't want to contribute to consumer society, so he eats for free whenever possible. Sometimes that means digging through Dumpsters behind grocery stores.

It's not as if this 23-year-old can't afford food. He grew up near Rice University, went to Lamar High School and now works at the Menil Collection. It's just that he's got strict principles -- and he needs to feed a lot of people.

For the last four years, Lyons has been involved with Food Not Bombs. Several times a week, about a dozen people gather together in downtown to share vegetarian food with the homeless. The grub comes from all kinds of places, including trash cans. Most discarded food, after all, is perfectly fine. Lyons and his friends eat it all the time.

Most of the participants in Food Not Bombs are vegans, i.e., people who eat no animal products: no meat, no dairy, no eggs, nada.

Freeganism is just the next logical step. Say you order veggie fare at Taco Bell; you just supported the same corporation that owns KFC. Hello, bean burrito. Bye-bye, birdie.

Anytime you buy anything, the logic goes, you're contributing to the problem, so the only way to keep your hands clean is to get them dirty, to dig around in the Dumpster and avoid consumerism as much as possible. And, hell, why not help out the homeless while you're at it?

The local chapter of FNB has been around for ten years; the national movement for 24. Most of its participants are idealistic youths.

"It's a good introduction for people -- it was for me -- into empowering yourself to be part of the solution," says Lyons. "Most 16- to 20-year-olds don't want to sit down and do paperwork or research or writing. So if they can run around with their friends on bikes and jump in Dumpsters and cook food together, it's not really work."

But it is a little dirty. Lyons says rats and cockroaches are never really a problem, but sometimes grocers share Dumpsters with other vendors, so motor oil and other contaminants get splattered on top of the food.

"That would get you sick and is also just gross," he says. "And rotten food is gross, but it's organic, so it's not that bad."

Dumpsters are grimy places, but freegans still follow the rules of etiquette when navigating them. Rule No. 1 is to never make more of a mess than necessary -- you don't want to spoil the goods for the next diver or, perhaps worse, draw undue attention from property owners. And No. 2, don't take more than you need.

"It's inefficient," says Lyons. "You've got to carry it home and then it rots in your house."

Looking out for your fellow divers is key.

"I was Dumpstering at this one place and there was this lady there who I've seen a lot throughout the years," he says. "And then this other guy who I've also seen over the years pulled up with his wife in his truck.

"We pretty much pulled everything usable out and divvied it up based on who needed what," he says. "We were all working together. All three of us just didn't want the food to go to waste."

Of course, there are those who don't see the magic of Dumpster-diving.

"I think, for some people, it's a matter of pride," says Lyons. "They don't want to feel like they have to do that. Society's view of garbage is that it's no longer anything but trash; it's dirty."

Sometimes even the homeless will pass up the free food offered by Food Not Bombs, once they learn where it's coming from.

"For some people the idea of a Dumpster is so foreign that it's a real turnoff. But then they see us eating it," he says. "I've always made it an absolute point to eat anything I'm even thinking about giving someone."

Lyons emphasizes that FNB doesn't forage in Dumpsters for table scraps. Day-old bread, veggies that have been replaced by slightly fresher ones, discarded sacks of flour -- this is the kind of stuff freegans are looking for.

"The food out of the Dumpster is perfectly good food," he says. Most of it just ends up there because of unnecessary waste. Apparently it's good business to keep a store constantly replenished, even when the food on the shelves is still nutritious.

Chichi grocery stores seem to be among the biggest offenders. Their Dumpsters offer bittersweet abundance for freegans.

"I'll eat anything out of the Dumpster," says Lyons, "but I wish it weren't there. I'd like eventually for our society to not have waste like that."

Store owners often go to great lengths to keep people from digging in the bins, even though they want nothing to do with what's inside.

"I think the mentality is that if people can get it for free, they won't buy it," Lyons says. "So the capitalist world or whatever doesn't want to make anything free available. Obviously, it's impractical to really care that much, but some places really do."