Commando Locks have been talked about here, so I'm only going to focus on something I did.
I recently got one of those, and was informed that you can remove the shackle by opening the lock CW, rotating the shackle 180º, and picking the lock CCW.
That was very cool to find out.
But I'm a strange person, and I wanted a key for it.
The regular key won't do it because the keyway has some lips that prevent the key to rotate backwards:

So, in order to do that, I had the key copied. Then I filed the part of it where it binded against those lips:

Success!


Now I can disassemble it without having to pick it (not that I mind to pick it anyway, but I like to have the keys

