I tend to have a few chicken breasts and a bag of prawns at all times to throw into things. When I have space, I dice up chicken before freezing it (not all my chick dishes need diced size, but lots do). The same with pork chops, I will sometime dice up some of them before freezing to thaw faster and cook straight from micro thawing.
Homemade stocks. I have seen the idea before as well that, if you don't have enough bones to make a meat stock, freeze the bones until you have more to add to it and enough to make a batch. And then freeze resultant stock, I mostly do it in half or full pint tubs, but I tend to do an ice tray of cubes as well, for when just small amounts are needed.
Scones, fairy cakes, breadcrumbs from leftover bread, a bag of plain stuffing made from more breadcrumbs (fast dinner of stuffed tomatoes is suddenly possible!!). Grated cheese (I saw a recommendation elsewhere onMN this week to grate up the odds and ends of different cheeses and freeze as a mix - I thought that was clever).
Freeze gluts of veg from garden or greengrocer when in season.
Stewed rhubarb, to just heat and serve. Stewed apple, ditto, or more usually to throw into a pie, maybe with a handful of frozen blackberries over the top.
Hm plain tomato sauce, I add the veg when reheating it. Spag Bol sauce is very versatile.
Can't think of anything else at the mo. Enjoy, I'd love a chest freezer.