Currently playing around with a Dell Optiplex SFF with a P4 1,5Ghz. Not really useable for production stuff ;)
Will try out my Core Duo laptop as a MD.
Plans on buying a HTPC - thinking a AMD X2 5000+ or more, mATX in the Antec NSK2400 case, with some sort of tuner - either a hauappauge analog one or possibly a hdHomeRun if its useable in Sweden.
Has a NAD-amplifier that would be nice to control from LinuxMCE. Might add support for this.
Lives in Sweden.