In Helsinki, where I live, the transportation system uses a card system which merely requires the card to be pressed against a sensitive area of the sensor machine. The card can be kept in a wallet or purse which can be held near the machine. As a former New York City resident who has missed many a subway train when the persnickity wipe technique was not in absolute conformity with the demands of the reader, I really appreciate the difference. I don't know if this type of card can be used as a credit card but it would simplify things.

Great idea, but needs more: There are other styles of card readers that suck in your card for a moment. Probably it is time to go for a RFID card.

Google: Mastercard PayPass

Just put a big triangle on the slot where the stripe pickup head is. Have the software in the manual stripe units be bidirectional.