A very simple custom treadmill I made for the workout room in Chris's fire station:
It's made using the pallet lift from
4135 - Super Set Construction Site. I just put the treads in the raised position, and then used sticky tack (earthquake putty) to attach a piece of black card paper. The handles are turned around so the person standing on it can reach them of course, and then the display screen is a laptop screen. Simple but effective! And the whole thing is attached only with putty so it can be easily taken apart and restored to its original use.