There is a really neat little device coming out now called ICache. I’m not sure I completely understand it yet, but from their web it seems that a prepaid card value can be instantly loaded to a generic mag stripe card.
“iCache is a small portable device housing a single card and display that can be used in place of any of the cards in your wallet – whether online or at retail locations.”
“Technically, you will be able to put any type of card that has a magstripe or barcode into your iCache. And, in case you’re wondering, a magstripe is that solid, usually black or silver stripe on the back of most cards in your wallet. Credit cards, debit cards, prepaid cards, ATM cards, loyalty cards, gas cards, and gift cards are all iCache compatible. You can even receive cards delivered electronically right into yout wallet! You can put pictures in your wallet as well!”
“When you want to use one of the cards in your wallet, just swipe your finger, select the card you would like to use from the menu and that’s it. The whole process takes less than 10 seconds.”