I love Goodwill! They have the coolest stuff. I get silver things from there all the time, clean them up in less than an hour, and sell them on eBay :)
Their book selection is always changing, and I've found some cool paintings there as well.
I was at Goodwill this morning with my sisters, and I happened upon this awesome twisted and pulled Canada Dry glass green bottle; it was only 3 bucks, so I bought it, now I'm wondering what I want to do with it ;)