I made a basket from bodega bags (also chick pea and other food bags). I guess I probably spent $1.20 on the crochet hook, though it's likely that my Mom gave it to me.
At some point I got so crazy about making them that I couldn't throw any plastic away. Friends, and later strangers would give me their old bags - sometimes they were really gross. Thankfully, I've now stopped making the baskets.