[joss82]

How can it give you your private IP address? I'm curious...

Is there a javascript call to list the IP addresses of any machine? That feels very insecure to me.

EDIT: Sorry I forgot to turn on my joke detector.

[jfr]

It probably gets it from the X-Forwarded-For HTTP reader inserted by his intranet proxy.

http://en.wikipedia.org/wiki/X-Forwarded-For