Sarc had a tibook with a broken LCD, so he removed it and uses an external monitor. From the MacNN forum post:
Since I operate the computer on “closed-lid” mode, I was having trouble keeping the LCD closed because it didn’t allow the heat to dissipate, so the fans where running constantly … I removed it. After it was gone, the computer would still think that it had an LCD attached. After a lot of Googling, I found on this helpful page that a magnet-operated sensor manages the ‘open’ or ‘closed’ status of the lid. The magnet was inside the lid, so I removed it and now its under the masking tape shown on Pic. 1. It has to be placed on that precise spot on top of the trackpad.