Not something I have ever really thought about before, but I just stumbled on a post on LifeHacker about How To Clean Your Credit Card and I guess it does make some sense if you are someone who constantly has to get a replacement card because the magnetic strip keeps refusing to swipe properly everytime you are in a shop with a queue of people behind you.

For myself it is always the signature and security code which tend go first and there is little I can think of (most obviously the use of clear nail polish) which will cure that problem without the risk of constant queries over whether you have tried to tamper with the card.

If anyone does have any suggestions, please let us know otherwise I will just have to continue eating shop assistants to get over my embarrassment at having my card rejected again.