Quiche - yes, cook it first, then cool and freeze. Straight into the oven from frozen, works well
Mash on pies - yes, you can freeze it, and then straight in oven from frozen.

Sausage rolls/pasties/pies
Lasagne/Pasta bakes
Meatballs/hamburger patties
Meatloaf
Filos
Curries

Came across a recipe for these baked rice cup things - basicall veg and cooked rice mixed together with cheese, eggs and ranch dressing (I used some cream cheese instead) and baked in cupcake pans with cheese on top. Turned out well and have frozen and reheated well. Super quick snack.