That sounds weally intewesting.
Sewiously though, the only way I can think of off-hand to do that would be for a specific map - i.e. you need to do some scripting to get it to behave that way - which is cool, but means you can't build a stand-alone plugin to play it on other maps.
Alas the game types are difficult to customize via plugins, which led to the koth flipper and balls o' fun, and subsequently to the uber-cool balls o' death - you can tweak a game ball somewhat because it acts as a "projectile" part of the time, and those can be tweaked.
But one never knows - now that the force known as VR has been unleashed upon the world of plugins...
