There are alot of threads on the best places to meet women (class, laundromat, grocery store, bars, etc) but no threads on the worst places to meet women. So I figure I should start the ball rolling.
I will second rehab. Although the hookup rate is amazingly high in the short term, the long term prognosis is horrible for both the relationship and the wellbeing of both participants.
Collector meets. Most things are collected by men only; the few women around will be attached. Some things are collected by women only; the few men around will be attached or effeminate.