Try Happy or Taboo on Sundays. I was at Happy on a Sunday in late Sept. Really crowded, but don't go there too early.

There is a place at 1 Fullerton (near Fullerton Hotel) which has gay nights on Sundays. Sorry, I can't remember the name. When I was there it was closed for renovation but I was told that it would open the following weekend.

Enjoy, SIN is fun.