SMBC is a pretty awesome online comic. I've known about it for a long time, but I didn't actually go through and read the comics beyond a slight skimming until recently, when a friend posted some excellent ones on Facebook. I especially like the science/engineering related comics. Duh. Here are a few choice favorites.
Hahaha, this next one is my favorite. So true.
So go read it. BECAUSE IT'S FUCKING AWESOME.