There is a nice free of charge NFC app at Android market. The author offers the source code as well.
Control your Android phone by NFC
NFC app features
- enable/disable air plane mode on tag detection
- start an external app on tag detection
- enable/disable Bluetooth on tag detection
- enable/disable WiFi on tag detection
- switch ring tone on/off on tag detection
- set alarm on tag detection
Read more here
I will use this news at my presentation at Droidcon in Berlin. Maybe we will meet each other on the 13th or 14th of March in Berlin as well.