You can glu something to it and then stick it on the fridge.
Whcih I will do. I will make from some old Playmobil toys, now nice magnetic memory magnet for the fridge.
Do keep them away dorm any creditcard of electronic device. i did a test and sperated them within 3-5 cm and they jumped together.
So speaking of some strong magnetic force!!
I made two picture to show the force and the size of it (50 eurocents, about 1,5 cm)