R2D2 is cute and all, but fact remains the little shit is a trouble maker. Sure it's a clever little droid, but when was the last time R2 served Luke an Altorian milk-ale? I'm guessing never.

Bar2D2 on the other hand is less cute and somehow more sinister than R2. It will get you wasted in about 10 minutes flat and maybe give you a seizure in the process. Sure it comes with a "beer elevator," but will it distract a Sith Lord while you make your escape? Probably not.

R2D2: Electronic fuck-up, or best friend?

Bar2D2: Best friend, or best way to get fucked up electronically?

The best part is that you can build both of them at home:

R Series Droids at Astromech
Bar Series Droids at Instructables