Maybe the best-known multitool the world has ever seen is the Swiss Army knife. The Victorinox Classic SD is not only one of the best-selling Swiss Army knives but it is also small enough to fit on your keychain.

This multitool may not have the 30 tools found on the larger models, but it does have the essentials. Just a few of the tools are a small blade, nail file, screwdriver, scissors, tweezers, and toothpick. When closed the tool is 2.5 inches.