The most catchy video game song of all time:

[XGamer0611]

Sonic 2 probably had the most catchy tunes I heard.

Here is my favorite: http://www.youtube.com/watch?v=TVEyGntyOZQ

 

Here are some honorable mentions:

http://www.youtube.com/watch?v=M-gocswLwsc&feature=related

http://www.youtube.com/watch?v=yRuJfhEeCe8&feature=related

http://www.youtube.com/watch?v=jl6kjAkVw_s&feature=related

http://www.youtube.com/watch?v=vKUcIaGvSmw&feature=related - By the way listen to the riff it sounds like "welcome to a whole new level of fun"