Friday night. You and your friends order two beers from the taps, a glass of wine and the frou frou cocktail of the night—you know, the one the bartender has to whisper to before he pours it over the back of a spoon. The check comes and it's blank stares all around at the empty tip line. Should you add 20% to the total? Do you just combine the dollar bills in everyone's pockets and call it a night? What I learned this week: the standard for tipping at the bar is $1 per drink. But it's not that simple. Let's take this matter to some well-liked bartenders around town for some straight shooting on the matter.