My wife & I were traveling BA F IAD-LHR-BKK in April 2008. When we arrived at T4 (BKK wasn't moved to T5 at the time) we went to check in a the F lounge. While the lady was verifying our boarding passes I noticed a guy on his hands and knees crawling between us and the desk toward the doors to the lounge. The lady noticed my stare and asked if something was the matter. I simply pointed to guy crawling and she came around to stop him. The guy then berated me for ratting him out. Then as he was at the edge of the terminal door he delivered his coup de gras "will you please guest me in!". I still laugh at scene.