I was wondering if anybody had a pic of the G-man's cell phone... i recall discussion about a scene in OP where he was using one. I never got the chance to see it. I would really appreciate it.
I don't know of any cellphone, but I'll have a look.
Heres a quote I found: Foxtrot Uniform (map: of5a4): After a battle with Race X aliens, Shephard arrives at the damaged Black Mesa hydroelectric dam. Standing on the inaccessible (except through use of the barnacle gun, this may be considered a glitch) control tower is the G-Man, who finishes a conversation on a cell phone and steps into a portal.
I would go there and take a screen shot, but I don't have Opposing Force on this computer. But the map name is at the top if you want to see for your self.
im guessing you mean this one 
Hm, G-Man with a cellphone. lol