Watch the video I think the title say it all!
I hacked my 1983 Tandy TRS-80 Model 100 Portable "Computer" with a TTL Bluetooth Module to control my EZ-Robot Wall-e. Why? Because it's awesome- that's why!
The source code for the serial relay server is in the EZ-SDK package. If you want to perform this hack yourself, you can see the pins that I connected the RX/TX bluetooth module to on the 6402. I put the terminal program in 9600 baud mode with COM:88N1D command on the TRS-80.
With this hack, you can also load programs over bluetooth to the TRS-80 using the Basic programming language. The command LOAD "COM:88N1D will load what ever is transfered over the bluetooth connection into the TRS-80 (Yes, do not use a closing quote in that command). When the program is done uploading (maybe through hyper terminal is good to use (copy and paste the code), press CTRL-Z.
Oh yeah, and Wall-e has wicked dance moves!