"is there any quiet, no-smoking bars or clubs in Beijing"
I think go to Tea House is perfectly appropriate~:p
Defeats the whole purpose of going out and having a good time.
stay at home.
if you want to go to quite places, you better go for places with a "Cafe" in its name which opens up late. Try Wudaoying for a change or the few bars between drum tower and bell tower.
BTW: GT Banana is not a bar, it's dance club or disco.
oh, Bookworm is a nice an quiet place to hangout if you dont want to leave typical foreigner corners.