BlueScan
via Mr Gooby, BlueScan: "Bluescan discovers nearby bluetooth devices and represents them on the screen as a cellphone icon (even though they may be PCs or other devices). As they are discovered, they appear at the top of the screen, then slowly drift down until they disappear at the bottom. Newly discovered devices are red, devices you've encountered before are green. The more times you encounter a device, the bigger the icon will be."