Beerdude's Signature is notable because it constitutes a potted, if incomplete history of HL2.net.
Encoded into the words of a quote - "I love spiders. I fantasize about their hairy little legs running wildly across my naked body" - the signature contains dozens of links to various pieces of forum history, including Biozeminades, Cat Got No Keys, the night Angry Lawyer was banned, The arena and the HL2.net comic. Its condensed format makes it very useful for nubs who've joined after the year 2003.
Beerdude's sig can be found at the foot of any post by Beerdude, unless he changes it.