Geeks Who Drink  and Buckfifty.org , two homegrown hits with the potential of becoming downright institutions, are bringing their posses together tonight for a special-occasion, locals-only pub quiz. Everyone is invited, of course, even if you're not a fully entrenched Denverite. (Two rounds of the eight-round quiz will not be locally specific.) If you've yet to experience the Geeks' unique brand of quizzing, let this be your initiation. Alongside the Buckfifty crew, you'll be in smart company. The games begin at 8 p.m. at Fado Irish Pub, 1735 19th St, downtown. Bring up to five friends for a team of six (the maximum). Or, if you insist, play alone. Winners score drinks--and status.