While I never have a problem finding something to buy with the gift cards I’m given, sometimes if they’re for a store (instead of a restaurant or entertainment) I have trouble getting something that’s exactly the right amount. (I don’t want to spend MORE than the gift card. So, I frequently wind up with something like 37 cents or a dollar nineteen left on the card.) When that happens I usually give the card to the person behind me in line. It cheers them up and saves me from carrying around the card ’til the next time I’m in the store.
If you have gift cards that you can’t use, you can sell or trade them on craigslist. You could also sell them on eBay, or swap them on a site like cardavenue.com for a fee. Or there’s always regifting! Especially if the card does not expire and you know a person who would shop at that place.
I’ve often thought though that there should be a way to donate the remaining balance or unused cards to charity, but the only place I could find that allowed that was not yet operational.