The Bluefruit can also act like an HID Keyboard (for devices that support BLE HID)
Can become a BLE Heart Rate Monitor (a standard profile for BLE) - you just need to add the pulse-detection circuitry
Turn it into a UriBeacon, the Google standard for Bluetooth LE beacons. Just power it and the 'Friend will bleep out a URL to any nearby devices with the UriBeacon app installed.
Built in over-the-air bootloading capability so we can keep you updated with the hottest new firmware. Use any Android or iOS device to get updates and install them!