Odds are this
was discussed, but I don't remember seeing it.
It should work with Mt. Gox / MyBitcoin API.
1. Go have a good dinner with friends.
2. Get the check.
3. Scan it with you smartphone (or input a total sum in USD)
4. Input N = number of people in the table besides you
5. Broadcast to them via NFC / bluetooth / QR whatever that you request a Bitcoin transaction.
6. You pay the check with your credit card / cash
7. They pay you back instantly via BTC
This is possible today with MyBitcoin smartphone client, but requires you to convert USD to BTC, divide by N, and then have everyone scan the QR code you generate. This would save all these steps and just split the bill instantly.