Update May 21, 2016: I’ve since replaced Slate with Hammerspoon.
If you’re attached to your keyboard (who isn’t?), you might just enjoy Slate - a window manager for Mac OS X that doesn’t suck balls. While it might not come with shiny tutorials (like Divvy and SizeUp), it truly shines when it comes to customization - and that’s what you really care about anyway, right?
Give it a try. You won’t regret it.