Park End, Ronnie.
AKA sticky carpet.
The shithole
Its now been rebranded as a Lava/Ignite. Still not been and don't intend to.
Coven has been gay for ages, it's not permanent, but for at least one night a week its bum bandit night. They do normal club nights too, and good live dance music.
As Ben Wah says, the Zodiac has become a larger O2 Academy so gets bigger name acts now. There's also the Regal which has opened up a bit further down the Cowley Road, massive capacity club which does some decent live music too.