I know on XBOX's that people make custom covers that extend the height so you can have another HDD in there. I'm supprised no one has made custom mini-lids.

/throws out a potentially profitable idea
MacBook 2GHz Intel Core 2 Duo w/ 2GB DDR2 RAM & 120GB SATA 5400RPM HDD
Canon Rebel XTI
Google Cr-48 Beta Laptop