I found a great use for my Iron Gym that I wasn't using anymore since I could not put it up on any door post in my new house.
It's perfect as a wall mount for my fixie :)
1. Turn the black plastic bar around to the other side of the metal bars (this normally sits on the opposite site of the door)
2. Drill two holes through the plastic
3. Attach to your wall with two fischer plugs, two large screws and two rings
4. move the foam on the bars a bit so it protects your bike
For heavier bikes I would recommend to put an extra wall connection that is used for pipes on each of the two vertical bars.