I never really understood wanting to put a computer in the dash of your car. The limited amount of space available forces some compromise on the system you can use. The in-day computer is available from a few places including a firm called Dashboard Devices that will unveil a new in-dash computer at CES 2009 called the ENV-XC.
The ENV-XC runs an Intel Core Duo 1.66GHz processor and offers 1GB of RAM and a 160GB HDD. The unit has dual FM RDS/TMC tuners and an option for built-in GSM/GPRS modems and more. The XC is designed to be coupled with in-dash displays like the ENV-100.
The display in the dash is a 7-inch touchscreen with a DVD/CD-RW built-in and a front USB port. The ENV-XC measures 1.77" x 4.25" x 6.61". GPS is integrated into the system as well. The machine is equipped with a hard drive heater for cold environments.