Geisha A Go Go is an awesome, inspired location for a birthday party. Specifically the private Karaoke room, but the whole bar is pretty cool. There is a random rock in the middle of the bar, which I'm convinced has more to do with tripping up drunks than it does feng shui. Drink menu highlights include Sakes and Sou-chus, loads of asian beers, and cocktails that look AWESOME (I haven't gotten drunk here, tragic!). Harajuko Lover? Yes please!
The Karaoke room is sweet, though the location of the pole is awkward and people sitting on the couches need to watch out for wildly flailing body parts as their drunk friends work it out. Maybe that's half the fun?
All in all a solid bet for a guaranteed hysterical night of karaoke, alcohol and dinosaurs in space. Or whatever other birthday theme you'd like to apply.