NFC - It's not just about the payment!
I worked on a patch to enable profile switching using NFC tabs with CM9, and it's now merged. This will be available in the upcoming builds for NFC enabled devices such as the Galaxy Nexus and Nexus S. Here's how it works..

1. Set up the profiles you like. A profile that I often use is a "Car" profile which disables the lockscreen.
2. Put a tag in this location (e.g. your car).
3. Select "Profile settings" then touch the settings icon for the profile you want to be able to toggle.
4. Touch the NFC icon on the bottom left.
5. You'll then be prompted to touch the phone to the tag you want to write. Hold the phone to the tag to write the profile information to it.

That's it. You can now simply tap your phone on this tag (when you get into your car) to enable the profile. Tapping it a second time will restore the previous profile (when you get out of your car).

Note that you need to unlock the device first, as with any other NFC code.
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