Here are some ideas of things to do with your old socks. Several of the ideas I found on urbanhomemaker.com.
1. Dusting. Old gym socks are great for dusting. Turn them inside out and slip on your hands. They are especially good for dusting the blinds, fan blades, furniture, etc.
2. Shining shoes (this works great and then you can toss the sock after using it a couple of times).
3. Sock puppets (lots of fun for kids).
4. Bean bags.
5. Heated rice bag. Fill a long sock with some rice. Sew the end shut. Then heat the sock in the microwave for about 30-60 seconds. This is great on sore muscles or around the neck as a portable heating pad.
6. Protect breakables when moving.
7. Cut the end off a pair of old socks. When painting, cover your shoes with the socks.
8. Cut off the end of a pair of old socks. When pruning roses or bushes with thorns, cover your arms with the socks. This will keep the thorns from scratching your arms. (Okay, I don't know if I actually would do this. It sounds like a fun idea if you like to look a little odd when doing yard work.)
9. Cleaning gross stuff. One good thing about old socks is if it gets really dirty from cleaning you can just throw it away. Using a sock on anything greasy or grimy (like stuff in the garage) is a good idea.
10. Hanging soap when camping. I've seen this when camping and it works really well. First, take an old pair of nylons and cut off one leg (or use a knee high stocking). Then put a bar of soap in the stocking. The stocking can be tied near the water spigot at the campground which makes it easy to clean your hands when camping. Plus you don't drop the soap on the dirty ground!
If you have any other good ideas for old socks, let me know! I'd like to try it out.