Arranger is a window management application. You can use it to arrange the windows of your active applications, or to create or arrange Finder windows. For more details and demo videos visit the developer page.
What's new in Arranger
Now you can arrange windows in thirds!
Hold down the Option/Cmd key while snapping to switch between halves/thirds (for left- and right-snapping only!)
Holding down the Option key while top-snapping will invert the setting for full-size/center