What to use to flip a light switch?

I like to automate things, but apartment owners rent too keen on you tearing apart things. So I'm going to use XBee to create a flipper. What would I use to flip the switch? A motor, servo, linear pusher?

A motor, servo, linear pusher?

I'd think a servo might be the easiest to start with.

I swapped the lightswitches in my last rental with these:
http://www.tlc-direct.co.uk/Main_Index/Wiring_Accessories_Menu_Index/Wiring_Accessories~Dimmers_All/Wiring_Accessories~Dimmers_5_Chrome/index.html

The landlord didn't notice / appreciated me upgrading the rental! easy to control with an infrared LED.