Here's a unique idea. The cool new Quirky Ribbon is a flexible silicone ribbon that controls the shape and size of your baking area. Instead of storing a bunch of different sized baking pans, just use the including steel baking sheet, shape the ribbon to whatever size your recipe calls for, in any shape you desire, and pour in your cake, brownie, pancake batter and more. The silicone ribbon is nonstick, oven safe and contains internal magnets that secure it to the baking sheet. Unfortunately, it's still in the design phase over at Quirky.com, but I hope it becomes a real product soon.
Silicone Baking Ribbon - Bake Any Shape