Chopsticks are useful not only for transferring food from the rice bowl into your mouth, but also for the following, extraordinarily helpful tasks:
1. Any type: beating eggs. Hold your hand stiff and the chopsticks open at an approximately 20 degree angle (yes, use a protractor). Beat eggs by moving the chopsticks rapidly in an ellipsis. I guarantee this makes less of a mess than using an egg whisk (which is bulkier and doesn't rest on a bowl easily), and faster.
2. Wooden: stirring, picking up dumplings and noodles, and similar manoeuvers from inside a pot or pan that's cooking. This includes a hot pot or shabu shabu (Asian fondu). You can also use it to poke through things like potatoes and beets, as well as into steamed dishes to check if they're done. Do not use plastic, ivory, metal or laminated chopsticks! They will either melt or burn your hands.
3. Long, wooden: for wok cooking. You'll easily find these 2 foot long things--sometimes joined on the ends by a string--near the cooking equipment. They will do all the things in #2 above, while protecting your hands from wok splatter.
4. Wooden: preparing live crabs. This will sound cruel to all you vegetarians out there, but is the traditional way to do it: when preparing live crabs to eat, you must remove the tail flap, stick a wooden chopstick up its &%$, and leave the crabs like that for about half an hour. According to my grandma, this is to let out dangerous intestinal and urinal fluids before cooking the crab.
5. Any type: saving space in your fridge. My grandma used to stack normal dishes in our tiny, Hong Kong sized fridge in our even tinier, Hong Kong sized kitchen by putting a couple of chopsticks across the top of each one as a divider. It works extraordinarily well--and saves you a couple of Tupperware to wash.