[ikawe]

I also found that sizeup mostly fills my WM needs on mac

In some ways I prefer it to strict tiling window management like awesome or xmonad.

You lose the "windows automatically tile" functionality, but the other side of that is that it's easier to break the paradigm for when you don't want to tile.

free unlimited trial: http://www.irradiatedsoftware.com/sizeup/

or $14 for a license

[osener]

Spectacle is a free open source application with the same feature set as SizeUp.

http://spectacleapp.com/