I like toast and peanut butter with an orange before a morning run. But before I moved to Colorado (the land of little air), I used to be able to eat anything before/during a run (except pizza or almonds, for some reason).

For super-long marathon training runs or trail runs that might take way longer than their mileage would suggest, I like to bring ginger candies along. Sometimes, if I'm not cramping because I ate something obviously stupid (like pizza) a kids-size soda will help me, too.

One other random hint - I believe gulping your drink of choice instead of sipping is supposed to help, also. I'm not positive about the science behind this but it seems to work for me. (I don't suggest this if the beverage of choice is the soda).