Once going into KLAX after a long flight from Europe my copilot and I saw what appeared to be an aircraft converging with us rapidly. We could see the green nav light on one side and the red on the other, but they were reversed from the norm.
We were close to taking evasive action when we realized it was two aircraft diverging in the distance rather than one aircraft getting closer. We laughed about it and carried on, but to both of us it looked like a converging aircraft until we recognized it was not - then we couldn't see how we thought it was converging.
I doubt we would've had that problem if we weren't coming off of a 14 hour duty day.