DebianUK
debian-uk is a mailing list and IRC channel (on irc.oftc.net) but mostly just a group of Debian users and developers in the UK.
What you don't know what Debian is? Go read www.debian.org straight away!
You don't know where the list is? http://www.chiark.greenend.org.uk/mailman/listinfo/debian-uk
Occasionally debian-uk people decide that this wiki is quite useful for storing random bits and bobs. This includes:
DebianExpoList (from 2002)