Smartphone "Tip-o-the-Day" posted a great Bluetooth trick:

Want a very fast way to enable (or disable) Bluetooth?

Bluetooth Toggle allows the least amount of keystrokes to accomplish this. It can be done with one keystroke (just add a single-digit speed-dial to this utility). Personally, I made it two keystrokes--"2" and "8" (for "B" and "T", BlueTooth, get it?). That way it is easy to remember.

Simply download the file, "BTToggle.CAB" from here:

http://www.modaco.com/index.php?showtopic=99493

and copy it to your phone. Click on this CAB file from your device to install it. After a quick installation, a shortcut to it is placed in the Accessories section of Start menu. Create a speed-dial shortcut to it and you're done.

If you are using a BT headset, this speed-dial can even be invoked while in the middle of a call.

[Via Smartphone "Tip-o-the-Day"]