Chris Denning's gay links database

AllGayUK (link broken?)

Cybersocket - keyword & category search

GayGlobe - category search

GayScape - directory by country and category

GayZoo - keyword & category search

HomoRama - fairly US-centric but all sites are reviewed

PinkLinks - UK search engine and directory

PlanetOut - news, discussion groups, search engine

Rainbow Query - keyword & category search