Play as Super Chun-Li:
Hold down start on her and wait more than 3 seconds and press any button

Evil Ryu:
Hold the start button for 3 seconds then let go. Move Right, Up, Down and then Left. Press and hold start again and press any punch or kick button.

Survival modes:
To start the Survival mode with Sodom as the first enemy: Hold down the L shift button while selecting your character.

To start the Survival mode with Ryu as your first enemy: Hold down the R shift button while selecting your character.

Rapid mode:
At the character select screen highlight the character you want to use and press and hold L+R+Start. When it says "fight" release those buttons and you should have rapid fire.

Win Pose Select:
Just before the announcers voice says "YOU WIN" hold down any button. Note: Certain characters have a certain number of poses. If you get a PERFECT with Chun-Li don't hold any button. Her winning pose will be her taunt which isn't selectable.

Thanks to Revolution readers Jesse Fish, Leonard Chang, Evan Merritt, Aditya Ari, M@GIC, and ntabot!