Well, to fund my hobby, I've been doing my best not to spend any money that I'm counting as income. By that I mean my last 2 audio additions have literally been bought in coins. Change saved up over the years that I cashed and spent on audio. Money from selling-back textbooks I also treat as partially-audio expendable (only half, the other half goes back into savings) because I have already factored it out as tuition costs. Other than that, It's all about hunting for deals and buying used. None of my setup was new, the headphones are modded, the speakers were free, etc. etc. Other than getting the turntable put together and building a dipole antenna for my radio, my only audio expenditure for a while will hopefully be music, lots and lots of used Cd's/vinyl from yard sales. Which can often be had for a buck a peice or so (especially if you offer to buy half their collection off of them)
As far as cooking: being able to cook helps a lot. It amazes me how much some of my friends will spend on food that doesn't taste that great (ram-en, dijorno pizza, lean cuisine) because they refuse to learn how to cook beyond the microwave. For the price of a frozen dinner, you can make make a nice sized pot of marinara sauce that freezes well, and yields about 10 individual servings of sauce or more. After that it's 30 cents of pasta a serving for good home-cooked food. Whole chickens are cheap too, and you get 2 breasts, 2 legs, and either chicken noodle soup or chicken salad out of them. That's 5-6 meals total out of a single bird, half an onion, a few stalks of celery and a carrot! Take that frozen toquitos!