Okay so I read this on a computer forum and got started earlier today. Yet to see any results but I shall see.
I found a good calculator and you can make some serious amounts of bitcoin with high end GPU's however the power cost makes it not worthwhile. Interestingly though living on campus I get free power and according to a calculator I found a 5970 graphics card could generate up to $13 a day. So if I get a cheap system (the rest of the hardware doesn't matter) and add a 6xxx graphics card, with free power I could pay for the hardware and start making decent money (plus its pretty cool in a nerdy way)