Before everyone harps on this guy for using snickers bars let me point out they are snickers MARATHON bars. They are significantly different. I've had them. Not only are they quite tasty (which to me is pretty important) but also have extremely high nutritive value. They provide excellent long term energy and good caloric/protein intake. Here's the nutritional info:

http://www.snickersmarathon.com/nutrition.asp

Plus, they're not anything really like the chocolate bars you see in stores so they hold together much better too.