I live for free in my fathers 2nd apartment, he also pays the bills so all my money goes on cocaine, beer and take away food.

I guess I could optimize a little better

I live alone, and rent is $650 per month.

My food budget is $10 a day, every day. This averages out to about $300 a month, give or take. I almost always eat at home.
I buy cheap meat and veggies in bulk at the supermarket, pre-cook it all at once, then freeze it in small portions so I don't have to worry about things going bad (plus it saves on gas). Most everything else I buy at the dollar store.

I also have a $100 discretionary fund, which goes toward everything that isn't food or rent (i.e. cigarettes, detergent, the occasional pair of shoes).

I rarely ever have to go anywhere that isn't walking distance, so my transportation budget is pretty much non-existent.

Whatever's left over (about $200 or $300 a month) I save for a rainy day, or for months when I'm a little short.

Unless I start making my own dough or give up smoking, there's very little else to optimize.