Shrove Tuesday (it was the 24th of Feb this year) is the day before Lent begins. Instead of throwing a huge crazy carnival to celebrate, the British would use up all of the rich food they had - eggs, sugar, butter, flour - and make pancakes. They're actually more like French crepes, just a little thicker.
It's the UK version of Mardi Gras, really. Anyway, we had a delicious Nutella & fruit crepe, sort of like the one you see here in this generic Internet photo:

We think that any holiday which encourages the eating of pancakes should be observed. So - get yourself some ingredients and whip up a batch of sugary pancakes and call it your Shrove Day pancake feast. Yum!