Gerber's “Dime” multi-tool isn't just pocket sized, it's keychain sized. This little guy manages to pack 10 useful tools into a tiny frame:

• Spring-loaded needlenose pliers
• Wire cutters
• Fine-edged blade
• Retail package opener
• Scissors
• Medium flathead screwdriver
• Crosshead driver
• Bottle opener
• Tweezers (removable)
• File (coarse body, fine tip)

There's a lanyard/keychain ring built into one of the handles so you actually can put it on your keychain to keep it always accessible. Just know that it's not TSA compliant due to the blade on that list, so don't try taking it through an airport.

Get the Gerber Dime for $25 on Amazon.