Pelican Keychain Flashlight / $16
There are lots of situations where you might want a flashlight — and might not want to use the one on your phone. With a compact size and waterproof build, the Pelican 1810 is a solid alternative. Powered by four LR 41 coin batteries, its LED bulb produces 16 lumens of light, plenty enough for small tasks. Its aluminum body is IPX4-certified against moisture intrusion and has a metal carabiner-style clip for attaching to a keychain so it's always available.
Length: 1.5" / Weight: 0.5 oz.