Good luck! Though I will add that a pre-modded case for a little more would have got you to that point already. If money was an issue, I understand and that's why you went with the $49 case.

Get fan grill covers, drop a 450w (atleast) P/S into it, variable fan speed switch, 2 cathodes (white or blue), get some Bondo and form an object (whatever you want) into the side or front of the case, and a switch that looks like it came from top gun as the power button. And a racing stripe...
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MacBook 2GHz Intel Core 2 Duo w/ 2GB DDR2 RAM & 120GB SATA 5400RPM HDD
Canon Rebel XTI
Google Cr-48 Beta Laptop