Imagine you are 11 years old, you are going to your local fish and
chip shop with a five pound note in your back pocket that has taken you all week to save and you are really excited and desperately looking forward to some beautiful fish and
chips. You are really excited but alas, as you walk out of the shop with the goods wrapped under your arm in newspaper, you drop it onto the
rain drenched road, the fish and
chips spilling everywhere...
Thus, when referring to a silmiar scenario, one can say "It's a fish and chip moment", or "That was a fish and chip moment."