I take a pepto and either pop in a funny movie or start reading a light-hearted book (Harry Potter is my favorite book to read when I feel nauseous). If that doesn't work, I start to pace and talk to my boyfriend while pacing. If THAT doesn't work I pace and read at the same time (hard to do, but possible) with the television on. I guess what it amounts to is that I try to overload my brain with other things to concentrate on, since 99% of my nausea is psychosomatic.
I suppose that's why I have such a hard time being in public when I get a nausea attack. You can't really do all that when you're on an airplane or at work or whatever. Still, I do my best.