Not by design, and not to any advantage for me, but I replaced the Z axis on a small Starmill with a plate driven on linear rails, and the wipers overshoot the top of the rail by a few millimetres before the legacy end-stop activates. It always worries me when homing the machine (the risk of exposing the balls) but it never has yet. Being at the top end of the Z it does give me a problem that random crap and dust could settle within the bounds of the wiper, but I never leave it there for very long.