Someone mailed me to request my spam filter system, so I packaged it up slightly with some command line arguments and documentation. You may download it here:
http://atari.saturn5.com/~jwb/spam-2.0.tar.gz
I added a --gram-length=n option, so you can play with that dimension of the system.
workrave
I recommend you try Workrave, to help keep your hands useful in later life.