Strong magnets are amazing. I have these
holding my hand tools to a light over my bench at work. The big black rectangular one on the far left of the image came out of an old hard drive and it is way strong. As in, you will have to twist hard to get it to move, nevermind pulling it straight off. WM found it because it jumped out of a pile of junk and clamped itself onto his little golf cart he drives around the warehouse. From several inches away.
I use it to hold up my 25 foot tape measure (as you can tell) but I just found another use for it. I wanted to clean off my bench and literally just tossed the razor blade in the general direction of the magnet. It stuck. Now I just have to remember not to pull the blade in a way that cuts my finger off when I try to get it off the magnet.