My son is 4, and he makes his own sandwiches--he has his own "knife"(one of those spreader things). He can pour his own cereal and milk(I put it in a smaller carton instead of the huge gallon so he can handle it). He helps peel eggs, mix batters and doughs and makes instant puddings. I don't let him actually "cook" yet, even in the microwave, but I'm sure nuking things is just around the corner lol!
It may sound strange, but I was pretty anal about teaching him a few basics as soon as I found out I was pregnant with him. Once as a child, my mom told me a story about a little boy whose mom died in her sleep, and he kept himself and his little brother alive for a while by eating peanut butter out of the jar(he'd stick his finger in and let the baby suck it off.)until they were found. The story stuck, and with me being a diabetic I wanted to be sure my boy would be okay! Go ahead, call me paranoid