Red Bull if I'm dancing; it keeps me dancing until sunrise. Order it on the rocks, of course (it's dreadful by itself), with citrus. And if the bartender asks what kind of citrus, say both lemon and lime.
Oh God! Not Sharps! There are, however some fine non-alcoholic brews around. Kaliber (Guiness), Becks N.A., Clausthaler, and Buckler (Heineken) are a few that come immediately to mind. Becks is my current favorite.
Why is it necessary to make excuses for not drinking alcohol?
Well, western civilization, historically, places a rather extraordinary emphasis on it.
Anyway I'd just get a coke or something. If you're not going to drink just accept that you're not going to drink. I don't really get the whole buying a non-alcoholic drink that looks like a hard one thing.