I love stopping at every garage/yard sale I can. I have bought several photography related things at the. Some of the highlights include a Manfrotto 190 Pro tripod (no head) for $25. A bag of miscellaneous filters and rubber lens hoods for $1 (that just so happened to include a 67mm circular polarizer.
A light/flash meter for $20.
I have probably 10+ old flash units that I picked up at garage sales or swap meets etc. Many of them don't work, but some of them do.
I have passed up on a lot of good stuff as well. For example, a Pentax 35mm system, with camera, 4 lenses, flash and other accessories for something like $40.
I do dream that one day I'll find a Leica for $5. To someone who doesn't know better, they don't look like much...so there is a chance. :roll: