Compact Travel Gear: 28 Must-Have Items for Your Luggage

The card includes an eyeglass screwdriver, letter opener, nail puller, ruler, bottle opener, can opener, box opener, cellphone stand, hex-head nut and bolts, screwdrivers, and a fruit peeler. Reviewers said it is TSA-approved, but some had to remove it from their bag and put it on the belt by itself just to be safe.

Promising review: "This is definitely helpful to have on hand! The Ninja is small and slim but punches above its weight class in terms of usefulness. The tools are all things you might find yourself searching through a drawer for and are useful in a pinch. You obviously aren't going to be able to construct a deck with anything on this credit-card-size device, but it fits comfortably in your wallet and will help you open a beer or tighten a screw. The coolest feature that I couldn't find on most other similar products was the credit card phone stand. It is great for planes and other travel applications (I haven't had trouble bringing this on a plane anywhere I have traveled, FYI)."—Mary

Get it from Amazon for $12.99+ (also available in packs of two, three, and five).