i just realized i'm using something equally as ghetto as your cardboard contraption.

it's basicaly two psu fans with contact tape on the bottom to hold them to a peice of art board, then there are two keys from an old keyboard to hold up my laptop and let air flow under it the keys also have contact tape to keep them adhered to the art board. i did sauder a switch to the fans, saudered that to a firewire cable and powered it by an old ipod power supply laugh

my powerbook runs alot cooler now :P
2.4gHz 15" MacBook Pro, 1.66gHz Core Duo Mac Mini, 2.5gHz G5 QUAD, 733mHz Quicksilver, 450mHz G4 Cube, 700mHz G3 iBook, 350mHz Sawtooth G4, 350mHz Revs. A and B B&W G3, 16mHz Powerbook 100, 8mHz Macitosh Classic.