bluetooth signal strength app?

Bluetooth Explorer is part of the developer tools set (XCode) located in /Developer/Applications/Utilities. The sig strength display is accessed in Bluetooth Explorer's Devices Menu, Connection Quality Monitor menu item. Click start and it will show the sig strenghts for the connected BT devices (look at the RSSI display). But I don't know how that's going to help you find your missing device 😕 (ok, I suppose you could move the machine around looking for the max strength)

If the laptop was not the original machine it was paired with you need to unpair it from that original machine and then re-pair with your laptop to see it. (or is it just to pair with it?).

I know your post is a bit old, but I had the same problem but the "time to connect" did not work for me. So I thought I would share with other people how I found the bluetooth headset that I lost in my appartment. It was quite a simple solution but it involved calling someone and getting their help. I called my friend and told her to put in earbuds or something so that she can hear me and text and the same time. I went around my whole appartment banging on a pot while I had the headset switched on. I had her text me as she heard it getting louder. Finally I got to the point where I knew I was near it and she said she could hear me talking so I simply started to talk to her as she responed via text. It was only a few minutes later that I was able to find it. For some weird reason, it was at the bottom of a bag of towels I keep under my sink for spills. I have a guess as to how it got there but it would have taken forever. Anyways, for those who have this same problem in the future, this is the best way to do it without having an app or computer trying to find the signal strength.

Jonny, you had the best solution, by far. I too had the same problem, also with a Plantronics Pro + (what is it about these things???).

I didn't even need to do the texting thing... had my wife sit in the bathroom with the cordless house phone (yes, old school, still have a landline) and call my cell phone which was still pairing with the headset. I set the cell phone down, and walked around describing where I was. One thing helped a bit.. at least with the plantronics, when you get far away from the headset the signal starts crackling. That helped me narrow the search to which floor the headset was on, I periodically moved the cell phone so she didn't hear crackling with the dead air. So, kept walking around and eventually ended up pulling pants on hangers out of the closet and found it in a pocket! When you get close, if the caller can talk loudly, you can sometimes faintly hear the earpiece on the headset too. Great idea. Try this one.