you guys have some stupid priced thrift stores.
I'm not trying to brag here but I've scored a few times and i only go maybe once a month. This summer i got an Araya road bike ($9.99)for my girlfriend that matched the one i found on the side of the road in a garbage pile that i ride. It just needed a front shifter cable and air in the tires otherwise was in perfect condition.
And my best score, A Motobeacane Mirage ($6.99 but i happened to catch it on the right day for whatever colored sticker it was to be 1/2 price so it was $3.63 after tax) again in perfect working order, just a little dirty and the bars had been flipped up bum style.

granted more often than not i do come up empty but i cant believe some of you guys find $150 vasities and such.