Today I not only discovered that a Dell Inspiron D800 and a Precision M60 are essentially the same laptop (identical/interchangable M/B) with a different BIOS and to turn a Precision M60 into a Inspiron D800 is as simple as flashing the BIOS using a "/forcetype" as a command-line argument at run-time of the bios binary. Furthermore it seems that some (specifically the D800) BIOS binaries will run on either win32 or MS-DOS, but to get the previously mentioned hack to work, you have to use MS-DOS.
WARNING: Try this at your own risk. I will not be held accountable in any way shape or form if you turn your Lappy into a brick!
UPDATE (20070329): It seems that Dell still use similar motherboards for their D820/M65 product lines, but the BIOS from a D820 cannot be flashed to an M65 by using the /forcetype command-line switch anymore. Way to go Dell.