Streets of Rage 3

There is a secret level select. http://soronline.classicgaming.gamespy.com/

There are secret motorbike levels. http://soronline.classicgaming.gamespy.com/

There is a secret basement area in Stage 6.

http://soronline.classicgaming.gamespy.com/sor3_round6.htm

http://www.youtube.com/watch?v=7tO4wvH9PAQ