Except 360 degree loops, like in Sonic. Nobody's made a good example of how to do that with the platform behavior yet. I'm quite certain that would require a custom engine.
Platform object needs to have an option for "sticky feet" that can be toggled on and off... this would make the player walk up walls, follow the contour of the ground, etc, rather than walk upright only and "bump" into walls or steep slopes.
If that could be added, it would make the platform object handle stuff like sonic games, or maybe some other high speed platform racer or spiderman adventure game.
The only other thing you could do is make a "physics" sonic lol... that would be even more aweome than making the "sticky feet" if someone could pull THAT off. xD