Grannyframe
This is a game about robot space ninjas basically. You get to run on walls, throw shuriken, and have super powers. Need I say more.
The PROS:
The game is fun; it feels nice to play, it's sylish, and possibly the most important thing it's free! The game is mission based and the missions don't take much time individually (maybe a few minutes per mission), but you can easly spend hours a day playing it. The community is really accepting, nice, and helpful to new players.
The CONS:
For every good thing there's some bad. Now to actually start having fun you are going to want to turn your mouse sensetivity way down and when I say down I mean way down. That thing is like trying to control an inflatable arm flailing tube man. There is a distinct possibility that you may spend hours a day playing this, and completely ignore things you need to do such as: pick up your children from school, or go to work. Also, the game early on is really convoluted, and might be a little hard to get into, so patience is required.