This script can be used to automatically add wiggle, smooth and loop expressions to any selected properties.
Watch the video tutorial and download pt_AutoExpress from aescripts.com
To run the script as an embedded panel, place the script in a folder called ScriptUI Panels, inside the Scripts folder. If there is no ScriptUI Panels folder in the Scripts folder, you'll need to create one. When you restart AE, you'll be able to select the script from the Windows menu.
The script requires After Effects CS3 or greater.