As a result of losing stuff and getting terribly confused, I've decided to create a new GPG/PGP key as of November 2009. This supercedes any and all previous keys for me - because I've lost or forgotten about previous ones, or similar terrible rubbishness.
My new key pair is 3072 bit RSA, created 2009-11-07 (Key ID 2682235B)
Key User Name: Matthew Fowler <matt.fowler@gmail.com>
Fingerprint: 3237 64EE E5C1 E86B 2EF9 4979 6CDF 6EF3 2682 235B
(But note this page isn't SSL protected, so key-and-sig could be tampered in transit or maybe The Man has compromised the server, or all sorts of scary things like that. In the event of an actual info-apocalypse, I'll try to sort out some key-signing-party action!)