It ain't beer unless it has Guiness on the label. Now THAT is beer!!
More accurately it is stout -- oops, just saw that ray had gotten that one.
For more fun add a glass of champagne to make a black velvet.
if you want something slightly lighter try Beamish.
If you want the scottish equivalent try MCewans 80 shilling (for the weak you can always go for the lighter 60, or 70 shilling).
Then of course you could always go the Belgian route - Chimay, KwaK, Delerium Tremens, etc...and the lambics such as Kriek (cherry beer).
If you are in Germany there a plenty of beers, same in France and the Caribbean is developing some good largers (Piton from St Lucia is pretty good, Trinidad and Tobago has some good beers though I don't remeber the names - must have been a good trip) another international larger is Finlands Lapin Kulta which is quite refreshing.
There is always the student blaster - Snakebit (half lager, half cider) or Bitter snakebite (half bitter, half cider).
personally I prefer a nice dry vodka martini with an olive ;-)