I found protein shakes really helpful. I had to force them down my throat, but I always felt better after getting some nutrients into my system. I could eat strawberries, too. It's important to drink a lot of water, and it will hit your stomach a lot better if it's room temperature.
Pedialyte is an electrolyte supplement for babies, and is a a lot easier on a churning stomach than Gatorade is. If you're losing fluids from either end it's a good idea to replenish your electrolytes.