We had a no-man's land foul the other night - first one I've ever seen or heard of in my 30 years on the field.
A's end lined up on the LOS but was standing perpindicular to the LOS instead of parallel. He is not a lineman (shoulders not parallel to the LOS), but he isn't a back either. My wing threw the flag and after the play says, "You'll never guess what I have."
It was probably the most exciting illegal formation call I've ever had!
It was a youth game (8th grade) so we stopped the game and had everyone line up and explained it to the players and coaches. Mainly to teach, but probably also to enjoy the moment a bit longer.