Buy Swing-A-Way Comfort Grip Jar Opener, $8 The manufacturers cite “leveraged twisting” and “spring-loaded power,” which sounds like some complex physics or dark magic.

The Swing-A-Way Easy-Crank Manual Can Opener is a solid option if you have fatigue in your wrists and hands or limited mobility that would prevent you from operating can openers with a twist knob.

I can easily say that every time I've used a can opener, this is how it went. Press the handles together to clamp the circular, metal blades down on the top of the can, inside the rim. Then, turn ...