Hi!
Here's a recipe I've put in the SpamBouncer that catches most of the spam with Geocities links I've been seeing. Most of that spam contains, not just a Geocities URL (not always uk.geocities.com), but also a query right after the domain and first slash. If you block that pattern, you'll catch a lot of spam. So far, I've seen *no* false positives -- in the SpamBouncer spamtrap or as complaints from users of SpamBouncer 2.1 beta.
SpamBouncer is a huge set of Procmail recipes, so anyone who uses Procmail might find this handy:
We see a lot comming in with plain http://geocities.com lately, so you might want to add that also.
Bye, Raymond.