Fitscales for android, sorry iPhone users, is one extremely cool app.

The app allows you to weigh yourself quickly and easily with a Wii Fit Balance Board and Bluetooth enabled Android device. Weighing yourself is as simple as starting FitScales, syncing the balance board then standing still on the board when FitScales is ready. You can optionally sync your weight with RunKeeper and/or FitBit for easy tracking. The app works on both phones and tablets.

I must admit my Wii Fit Balance Board was gathering dust. Now I have a reason to use it.