I was not very happy with the existing solutions, so I just created my own.
The workflow itself is quite simple just typ in the keyword "lay" (or chose another of your liking) followed by:
full = Maximize
left, right, top, bottom = Halves of screen
topleft, topright, bottomleft, bottomright = Quaters of screen
11,12,13,21,22,23,31,32,33 = Thrids of screen
11-12,11-13,11-21,11-22 ... = Some other sizes based on thrids
... well the script is quite flexible, so I'm waiting for suggestions
For MacOS 10.8 (Mountain Lion):
The workflow itself can be found here:
https://github.com/untoldwind/alfred2-layout/raw/1.0_Mountain_Lion/Layout.alfredworkflow
and (obviously) its sources here:
https://github.com/untoldwind/alfred2-layout
For MacOS 10.9 (Mavericks):
The version above does not work (unluckily). An alternative (though somewhat experimental) version can be found here:
Release: https://github.com/untoldwind/alfred2-layout/raw/1.1_Mavericks/Layout.alfredworkflow
Experimental (Bleeding edge): https://github.com/untoldwind/alfred2-layout/raw/master/Layout.alfredworkflow
By the way: It is multi-screen-able. Even though you cannot move windows from one screen to another (yet?) the scripts tries to figure out with screen you mean (depending on the size of the visible area).
A short note about the implementation:
The script is written in python using PyObjC and the ScriptingBridge. This should be no problem as both is shiped as part of MacOS since 10.5.
It the application supports scripting, the window is moved "directly". Unluckily some Applications do not support this, so there is a fallback using "SystemEvents". This only works if you have UI scripting enabled: http://www.macosxautomation.com/applescript/uiscripting/For 10.9 (Mavericks) this has slightly changed. A more detailed description can be found here: http://www.tekrevue.com/2013/06/25/how-to-enable-access-for-assistive-devices-in-os-x-mavericks/
In our case "Alfred 2" requires UIScripting access
At the moment there are no hotkeys defined, which should be straight forward though