If you're keeping roasting trays, muffin pans and other baking items flat in a cupboard, chances are you're making life tougher for yourself than necessary. Storing them vertically makes it easier to grab the one you want and won't take up any more room.
The Oprah.com site highlights this trick and suggests using a rack, but you can actually do the same thing by simply keeping trays upright in a cupboard (as I do). Either way, it's easy to select the one you need. (That's obviously not an option if you're using a drawer, but chances are in that case the drawer is relatively shallow anyway.)
Think Slots, Not Stacks [Oprah.com]