I tried once with earth magnets, cost me dearly to get some... But I found they gave me sh%t with my personal stuff... (bank cards, telephone, etc.)
I can get hold of some VERY decent magnets which though small are quite powerful, very fragile though. and once they break... it's bye bye to the magnetism.
I'll give it a serious thought and try! If I get lost I'll know where to find you Jason-078. Hope you don't mind!