I have been looking for ways to recycle those pesky shopping bags. We save them all. If they have holes in them, I return them to a local grocer for recycling. At home, we use them for small trash can liners instead of buying boxes of plastic bags. I usually try to remember to take cloth or reusable bags with me when I do go shopping, but I don't always remember.
I have looked into crocheting them, but I don't know how to crochet. I've tried, but my fingers won't cooperate. I thought about making "plastic fabric" by ironing them together, then I read about the fumes created when they are heated....duh.
I take my lunch to work in one.
I've used them for shoe covers while in the garden, but they got wet and I slipped and fell. Ouch.
I use them to pick up "gifts" left by my dogs and cats.
We keep a couple in the vehicle for carsickness. They have come in handy for that a time or two.
We use one to take extra dog food with us when we travel. Allows us to store neatly under the seat and hang on the side of the truck or trailer when we reach our destination to keep the dogs from helping themselves.
They do make good rain hats in a pinch.
We use one in the truck for a trash collector.
We use them for padding when we ship something.
We reuse our collection when we set up at flea markets and other places to put purchases in for our customers if they don't have their own bags.
They are good for putting muddy/wet shoes/clothes in for traveling. Just make sure you empty them as soon as you get home. I forgot about a bag in the covered bed of my truck last summer and my son lost a pair of socks, tennis shoes and swim shorts due to mold! GROSS!
There are definitely more options, but these are just a few that I have thought about or tried. Feel free to post your ideas!