Speaking of Braille cards, here is a credit card concept design that shows the amount that has been paid in Braille on the credit card. The designer of this card thinks that having a Braille credit card can provide benefits to visually impaired users in a couple of ways in that with a regular credit card, they have to depend on the person behind the counter telling them what the actual amount to be charged is. The amount that they tell the user may be incorrect. The braille credit card, however, embosses the amount charged on the card so that the user could feel it. Also, the credit card has a built in speaker that can speak out the amount charged at the push of a button.
Another interesting Braille prototype.