There are thousands, millions, of ways to describe our world as opposing dualities: ‘Can’t do’ folks versus ‘Can do’ folks; foodies versus refuelers; Patriots fans versus the other 98% of Americans. It’s fun to figure out which camp I occupy (Can do, refueler, Pats fan). But even more, I enjoy discovering new ways to characterize our bizarre society, and get a glimpse at how the other side, however defined, operates.

Lately I’ve clicked into a fascinating corner of Craigslist: For Sale by Owner / Free Stuff. It’s a whole world of peeps that want to give stuff away, and peeps that flock after it.

I find garage sales tedious exercises in sorting, labeling, and bargaining over a quarter; I extract no joy in squeezing out a final tidbit of value from something that’s exhausted its value to me; yet my recycling gene rebels against tossing anything in a garbage can. All of which makes me the ideal candidate to offer up leftovers on Craigslist: For Sale by Owner / Free Stuff. Although I make no money on these transactions, interacting with the folks seeking free stuff offers a profitable study in human nature.

First thing to understand: whatever you don’t want, somebody else does. I have given away scrap wood, rotten wood, old magazines, rusty saws, and all manner of broken appliances. True, I could not find a taker for plaster ceiling debris, but that’s a mighty low threshold of utility.

Second thing to realize: how many people troll this stuff. I found four tires in my tenants’ basement. I know nothing about automobile tires, so I posted pics of the detailed data embossed on the sides. Within hours, dozens of people wanted my Bridgestone Studless / Tubeless Steel Belted Radials Blizzak WS-15 195/60 R15 8800 / K9304. If so many people want such a specific item in so short a time, how many people are spending their days noodling through Craigslist? Apparently quite a few.

Third, the stuff goes fast. Post an old lawnmower, tracks for ceiling lights, and cross-country skis: gone within an hour.

The most challenging thing about Craigslist is this: when you have a hot item—i.e. anything more substantial than plaster dust—how do you actually give it away? If I put it on the curb and post, ‘First come, first serve’ I incite a parade of vehicles along Fountain Terrace and generate more environmental damage than I avert by giving my excess away. It’s wasteful; it’s rude. If I offer it to the first person that responds and then pull the ad, more often than not the bloke won’t show. Free stuff ain’t worth much, and once a guy’s promised a free hacksaw, he’s in no rush to claim it.

Here’s what I do. First person to request something gets sole privilege to pick it up, for a period of three to four hours. Forget about the Wednesday afternoon gent who swears he’ll collect that table saw on Saturday morning; I’d be a chump to hold it that long. Being first in line carries some privilege, but there are statutes of limitations on the prize.

Once I’ve offered the item to someone, all other inquiries receive a standard email response that the has been claimed, but if it’s not picked up in agreed time, I will offer it to the next person in the order requests are received.

Time passes. The first, or second, or maybe even the third responder swings by to pick up that electric air pump. When it’s gone, I delete the ad and send every respondent a follow-up message: Thank you for your interest, the item has been claimed.

All this correspondence takes a bit of work, but in the game of Craigslist, I try to be fair. Folks appreciate it. I get follow-up emails from the woman who didn’t respond fast enough to claim those Nalgene bottles and the guy who missed out on the toaster oven, thanking me for being informative and fair. Because even though we can divvy up the world between those who post on Craigslist: For Sale by Owner / Free Stuff and those who seek what’s offered, everyone appreciates being treated as if our time and our pursuits warrant respect.