You can exploit inefficiency in non-equity markets, of course. Here is a way to get screaming bargains on used kayaks from craigslist.

I wrote this Ruby port of Jeremy Zawodny’s similar Perl script. It runs every 20 minutes, notifying me by email of new postings likely to interest me.

The result is effective, but potentially creepy: you post an item on Craigslist, and your phone rings 5 minutes later with my offer to buy. This freaks a few people out.

Using this method, I bought a nearly new $1500 sea kayak for $600, and a well-maintained $1200 Stairmaster for $200. Beneficial deflation in action.

(You could do this with an RSS reader, as craigslist can publish your search as a feed. But I always forget to check RSS. By contrast, nothing shakes you by the lapels like an incoming email saying, “bargain here.”)

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