Lock

I usually keep my uni hanging on a hook on the wall in my garage. I doubt anyone would break in just to steal it, but I could imagine it might catch someone's eye as something interesting or funny to take.
Plus I never know when one of the kids' friends might be over and think it's okay to take down and give a try.

So I put a bar on the wall to give me something to lock it to. I used pipe and U-lock: