I am in self catered accommodation so I end up spending most of my money on food. It's annoying but when you are self catered you have to control your entire diet so what you eat and how you organise meals depends on how much you spend. After that it'd be money for nights out. drinks and outfits for nights out.
Probably alcohol. I've found that if you're hungry, you can either sleep or get drunk. Both work quite well. Especially now that uni has ended for the summer I drink probably far more than I should. Being drunk for a good 3 or 4 days straight is pretty standard nowadays. Other than that I spend money on food. Fooooood.