If you think you have seen it all ... check out the NFC Ring on Kickstarter
Found this fun project on Kickstarter, shows the interest in NFC with meeting its fund raising goal in 3 days. John McLear was looking for 30,000GBP and is at nearly 90,000GBP at the time of writing!
From their site we saw "The NFC Ring can be used to unlock doors, mobile phones and to transfer information and link people." AND it is open source. Of course you can do all the above with any NFC tag bought right here, but it is good fun to see how these clever folks are putting into an every day use.
Keep in touch with the project, you might even want to support it. Good luck NFC Ring! Go you good thing.