I too have a lombard (A slower pismo with no firewire, but with SCSI), but alas, the keyboard is dead. Here is what I've done to it:
1 - Classic paint mod - Everyone's done this before, all that it is is spraying the hard plastic bits blue and putting some blue plastic under the apple

2 - Car Linux Audio player! I installed Debian and got a CrystalFontz LCD, and set up an audio jukebox, which I plan to install in my car in the upcomming weeks. I'll post a full how-to mod here when I install it, but for now I have A work-in-progress photo gallery

You could also make it into a set top box, using the LCD, or make it into a single use machine, like how I turned and almost-dead-ibook into a DDR box (no screen or keyboard).

I'd be interested in seeing a Lombard/Pismo mounted in a car with the screen on a seatback though, since the large screen would be perfect for in car movies