There is a new laptop component standard from Intel: "Common Building Block".
Perhaps Dennis, Jens S. or other can create Laptop motherboard based on FPGA. For Input/Output, they can use UWB Wireless USB: detachable keyboard, mouse, audio, LAN, HDTV/Digital TV output etc.
Another idea is using USB dongle with PC laptop, similar to Project Blackdog (Virtex FPGA with PowerPC 405).