Are you keyboard junkie like myself? Have a ton of finder windows open or trying to copy and paste from one document to another... or some other unorthodox reason for needing window management? Yeah... me too. I've used several of the window management apps, they are all very cool and have a really cool feature set about them, but still can't justify the price? Yeah... me too.
I've converted this Alfred extension from http://projects.jga.me/layouts/#toc3 to a workflow that uses both Hotkeys and Keyword trigger to help manage the top most window on your screen. Take a look at a look at Greg Allen's write up to learn how to use it. I only added a couple of hotkeys but feel free to edit to match your needs.
If you already own a window manager like SizeUp take a look at Carlos-Sz - SizeUp workflow