I think NFC is missing its mark - to me, the obvious use for NFC isn't device-to-device connections and sending files and all that, but for peripherals. One-step bluetooth pairing with an NFC tag would be lovely, right? Just bump-and-pair.

For gaming - imagine a game console with mix-and-match one-handed controllers. Trackballs, joysticks, pointers, keyboards, mice, etc. Bump them together to tell the console "I'm using the whamblefloog with the xorchball" so it can tie each disparate controller to the concept of a two-handed player.