super mario pipe physics?

i wanna know how you would be able to stand on a certain object(pipe), and press the down key to enter it? Could someone please help? any help will be greatly appreciated!

You should fool around more with Unity3D, and perhaps learn C#, Javascript, Boo, if you're not already equipped with experience. The easiest way I could think to do this off the top of my head, would be to attach a script to the pipe, have it check when the character GameObject is colliding with it, then have have it check if the Down Key is being pressed, if-so, disable the pipe's collision, add a Coroutine, and programmatically animate the players slow decent into the pipe