Canadian beers - Moosehead, KLB, Steamwhistle, Sleeman, Keiths, just to name a few
American - I'll drink Bud if i'm already drunk (plus its usualyl cheap at clubs for some reason), but for taste I think I'd have to go with Sam Adams
Irish - That one is easy, Harp and Guinness
European (and the rest really) - Hoegaarden has quite a refeshing taste, Becks, Heinkien, etc.
Smoke... can't stand the stuff.