As featured on slashdot, this is one amazing car mod! Read more about it below...
The basic two reasons that led me to the installation of the computer were the replacement of CD changer by an MP3 player and a navigation solution, based on Route 66 application. I am pretty sure anyone who needs to make 1000 km trips every month or has ever been lost in Copenhagen can understand these two reasons :-) During the installation, I also added some more functions (communication with engine controller, on-board micrcontroller for basic telemetric data). Of course I could simply buy a head unit that supports MP3 playback and a dedicated navigation hardware. However I was not very excited about the prospect of spending several thousands euro for a dedicated hardware and then wait for the manufacturer to release the maps I needed (Czech republic in particular). Use of standard computer gives me much more freedom in the configuration of the system and potential upgrades - both software and hardware.
The first idea was to use an LCD iMac, and built it into the original dashboard. The base unit was supposed to be placed within the dashboard and the display with its holder outside. This idea had two basic flaws: iMac"s 15" screen is really a bit too big for dashboard and its parameters are not good enough for use in full daylight (not to mention direct sunlight).
OK, so no iMac. The second alternative was a separate LCD display, built into the original dashboard and connected to a computer (either a PowerMac or a PowerBook), that could be placed under front seats or behind the dashboard. At this time, I also came with idea of another screen, that would allow rear seat passengers to watch movies or play games. This eliminated the PowerBook (since it cannot easily handle two external screens). So I purchased an old PowerMac G4/450MHz and a industrial 6.5" LCD screen, that has contrast and temperature range, which are both necessary for in-car use. The native resolution of this LCD is 640x480 pixels, but its controller can interpolate various other resolutions. I have chosen 800x600 pixels, which is the minimal resolution, required by Route 66.