Facetime Applescript Edit
It appears to be doable. From 

http://www.macosxautomation.com/applescript/firsttutorial/11.html

To get the application/windows dimensions

tell application "Finder" to get the bounds of the front window
--&gt; returns something like: {72, 90, 512, 481}


to change it

tell application "Finder" to set the bounds of the front Finder window to {24, 96, 524, 396}


and to find the dimensions of your display

tell application "Finder" to get the bounds of the window of the desktop
--&gt; returns: {0, 0, 1920, 1200}