The current series Nokia/Microsoft charging pads have NFC because they also have Bluetooth, the NFC is just a more convenient means for pairing the bluetooth connection. Once the phone is paired to your pad, the charging light will blink or flicker when your phone is running out of juice and needs a charge.
Due to the security limitations of WP8.1, NFC has limited ability to change settings on your phone. So, unfortunately, I don't think you can silence your phone with an NFC tag. This is an area I hope they improve with Wp10. Even if you have to check a box in the phone to allow an "Advanced" mode, I'd love the option to modify more phone settings with NFC.