Dulouz: I make mine with ground almonds instead of flour. Tastier and healthier.

networkn:

andrew027: My (English) mother always made crumble with just flour, sugar and butter but my (Kiwi) wife always uses rolled oats as well. I've tried to get her to stop but she's never known any other way. I've also struggled to get her to stop putting feijoas into them - give me a good old apple and rhubarb crumble like mother used to make. 

OMG Feijoa Crumble is the best!