I recently started bringing my own bags to stores because a) my cupboards were overflowing with plastic bags and b) frequent trade show attendance gets you lots of high quality cloth bags. I've been wanting to use my own bags for a long time now but I always forgot to bring the bags. Sometimes I'd bring the bags and then leave them in the car.
Anyway, I found out that Target will refund you a nickle for every bag you bring. It doesn't sound like a lot but I shop at Target a lot, mayb 2-3 times a month. It probably totals about 10 bags a month and so I'd save 50 cents per month or $6/year. So far my grocery store (Safeway) doesn't refund for plastic bags but other grocery stores do. I figure I could probably save about $20/year by using my own bags, help the environment, and cut down on the plastic bag clutter in my house. It doesn't sound like a lot but with a job situation in jeopardy, every little bit helps.