Don't see how I'd be picking it up unless it was on the same network as me. (I'm at home, admittedly in a flat with people in all directions from me, but on my own network with a non-trivial wpa2 key)
Significant number of random alphanumeric characters, mixed case
Didn't you root that phone?
Can't be bothered looking back, but have you turned off bluetooth on your laptop?
Yup.
If it wasn't for the first one showing up in my router config I'd happily believe it was just windows being odd. The weird thing is that all four devices have had different Mac addresses though. Very strange.
It's 4 totally different devices. Have any of your phones in the house shown up?