I have a situation at hand; I am running Mac OS X 10.8.4.
Today I observed a different icon on my Mac status bar. When I clicked on it it showed the name of computer of our vendor organization (a few members sit in our office). My bluetooth was on and I am connected to the LAN.
I searched on the net but couldn't find what this symbol means and if there was any attempt to get illegal access to my Mac. I have pretty sensitive data. Please help; if there was any access how can I see the log?