Beer Mixed Drink Recipes

common bar drink recipes?
I just became a waiter at the local bar, and that in a little personal. I know my beers and mixed drinks a few, but what are the most common drinks and recipes? I really want to memorize these, so do not look like a tool in the toolbar.
There are drinks that are not very common in a local bar to call liquor and liquor. My two favorites are a black Russian and a rusty nail. Always pour at least twice as much liquor. The Russian black is two parts vodka kahlua to one side and the nail is two parts whiskey and one part Drambuie. The excess of liquor that are too sweet. And always pour the liquor first.
Beer Mixed Drinks: Part 2 : How to Make the Root Beer Barrel Mixed Drink