no jumping but to get up to the top of a building, you ride the elevators. It doesn't have to be special, just like a block of land that goes up and down (that way no one can get stuck underneath 
). No need for doors or anything, just a simple steel/concrete block that moves up and down. How would it know when to go up or down? Maybe it could be timed. Maybe there could be a trigger. Maybe there could be a trigger on one end that would be pressed when everyone got on (basically just one person rides over this "zone") and that took them up. Then, it either is timed at the top or there is a sensor to know when everone got off to go back down. Or, there could be a button on the front of the elevator (like a welcome mat at a home) for someone to trigger the evelator to their position (whether on the bottom or top).
I'll have to make a 3d animation for you guys. It would just take mapmaking and general gameplay to a whole new level! Sorry about thinking BF2 for a bit but I do think it would make a good addition available. And it could only be a two level evelator (top and bottom).
