AWN Window Manager (also known as Tile Windows) is a new Avant Window Navigator applet which can be used to tile (side-by-side, staked or grid) or maximize all windows (as well as the usual minimize/maximize/close/show desktop actions) and comes with a preferences dialog where you can set the default left / middle click behavior.
Because I find it to be an extremely useful AWN applet, I've used Hadret's debianization of the DockBarX AWN applet for AWN Window Manager and uploaded it to the WebUpd8 PPA so you can easily install it in Ubuntu (9.10, 10.04 and 10.10). Before installing, please note that while in theory the applet should work with Avant Window Navigator 0.4, I've only tested it with Avant Window Manager 0.4.1+ from the AWN PPA (installation instructions HERE).
To install AWN Window Manager in Ubuntu, use the following commands in a terminal:
sudo add-apt-repository ppa:nilarimogard/webupd8 sudo apt-get update sudo apt-get install awn-applet-wm
If you don't want to add the PPA, you can manually download the deb: awn-applet-wm_0.5-1~webupd8~maverick2_all.deb (8.2 KiB) (don't worry about "maverick" in the version name, it will work on any Ubuntu version where AWN 0.4 or 0.4.1 is installed).
Once installed, go to the Avant Window Manager Preferences and on the "Applets" tab, scroll down to the "Window Manager" applet and activate it.
If you're not using Ubuntu, you can grab the AWN Window Manager Applet source code from Launchpad.