My newest wow-this-really-works gadget is the BottleTop — it snaps on to the top of a standard-size soda or juice can, effectively turning it into a resealable bottle. And it really does work; I had plenty of opportunities to test it out recently, during a weekend-long family party, and not only did it contain spills, it kept half-consumed cans of soda fizzy for ages. The washable and reusable tops come in different colors, making it easy to keep track of whose drink was whose; to remove, just crush the can a little bit and the top pops right off.

$10 for a set of 12 at Walgreens stores and online at BuyBottleTop.com.