I now have a Raspberry Pi model B.
A fantastically small device with more power that a lot of the machines I've used over the years. currently I am tinkering with getting XBMC, or rather RaspBMC working on it and Samba with USB drives.
It's going to take a while not least because of random crashes which seem to affect a lot of owners.
Once I've got something stable working I'll be able to experiment with the python programming and maybe get a little MySQL server running.
More when I make some progress.