1. Arch-shaped cookie cutter.
2. Citrus juicer, the kind that you insert directly into a piece of citrus fruit, not sure how well it works.
3. Top popper, for opening pop-top cans, so you don't damage your fingernails.
4. Another popper, looks like it might also work on glass pop bottles, and it even has a key ring.
Take any or all of these items.