Zombie Typomaniac is probably the only game on Facebook that uses creepy zombies to teach you a valuable skill. In this HTML5 game, a multitude of zombies advance toward you with words over their heads. Typing the word will kill the associated zombie, saving you from potentially losing that round. The game gets extraordinarily fast paced depending how good you are at typing on the keyboard, and I found it to be strangely compelling and addicting.
Space in Trouble is a clone of Taito's Space Invaders that suffers from sluggish controls. Games like this were once common enough, particularly in the early 80s when there was a huge market for fast-paced Space Invaders variations like Namco's Galaga. To encounter one in 2011 is shocking, even on Facebook. If Space in Trouble was presented to a computer science professor as a proof-of-concept coding project, it would not deserve a grade any higher than a B. That something like this was published with the expectation that people would spend money on playing it ad-free is almost unthinkable.