My highboy desk already has a few secret compartments. The desk was my grandmothers; I bought it at the estate sale. Most of my grandmother’s important papers could not be found. I eventually found the paperwork in the secret compartments hidden in the desk.
The desk now houses my pen collection. I wanted to hide the only key - close by (instead of leaving it in one of the three locks). I came up with the idea of using a magnet and tin to hide the key.

Step 1: Placing the Magnet

I happen to have some strong rare earth magnets that I got out of computer hard drives.
I am using the magnet in conjunction with a metal candy tin to hold the desk key.
I pulled out the bottom drawer; the board that is under the drawer is a dust board.
There is not anything more than placing the magnet down on top of the dust board.
I replaced the bottom drawer.
The magnet is strong enough to hold the key in the tin out of sight under the desk.

Step 2: Hiding the Key

I did not need to secure the magnet.
Just by putting the tin in the general magnet area, I can feel the pull on the tin.
I just let go of the tin.

Easy Peasy Lemon Squeezy.