This Geico commercial was one of the first to use the famous "money with googly eyes" which has proven to be a very successful campaign.

The catchy old school song "somebody's watching me" sticks in the viewers head, the stack of money with the googly eyes is a recognizable character (which also gets the unique selling point to the viewer in clever fashion) and the use of humor adds likability to the commercials.

This particular commercial is one of my personal favorites with the waiter yelling Geico to the camera abruptly to que the music. Makes me crack up everytime, and its effective!

http://www.youtube.com/watch?v=jlwjIhHMWLQ