Even though I've had some close calls, this one was pretty much the most interesting one...
It was pre-9/11. It was a flight AMS-SIN on KL in C. Luckily, the KLM staff is always very concerned about their late passengers and they go look for them by teaming up and walking all the way back to the main terminal (alongside the people movers) constantly shouting the name of the passenger(s) who is late, asking everyone they see who they are and whether they are on the flight they're working on. ^
I was already on my way to the gate as I heard my name being called over the PA (the famous "Kah ay lam" mispronunciation, but I digress) as a very attractive girl (about my age) was approached me in one of those carts that you see at AMS. She allowed me to jump on, but I fell down, right on my face!
By the time I was up again and inspecting the damage that occured (bleedy and swelling lower lip) the gate agents came up to me and held the flight for a couple of minutes. I just had to be on the flight, so after being handed some tissues I runned the jetway into the 747 and sat down in my seat. Can you imagine how my seatmate must have felt? (I was bleeding, sweating and out of breath, and not to mention terribly late!).
It did make for some interesting conversation with my seatmate and the purser though!