I designed a third multi-tool inspired by Doctor Who's Sonic Screwdriver. It is built with a butane torch, a laser/UV/flashlight, a magnet, and a label. It has many uses, including (but not limited to)
-Lighting Fires
-Brazing/Soldering
-Cutting
-Burning
-Melting (including some metals)
-Cauterization
-Cooking
-Scaring Animals
-Dazzling Opponents
-Flashlight
-Blinding Security Cameras
-Laser Pointing
-Emergency Beacon
-Scanning for Biological Residue
-Find clogged pores
-Detect Scorpions
-Reading Invisible Ink
-Opening Bottles
-Activate glow-in-the-dark items
-Determine if dollars are real
-Determine if IDs are real
-UV Curing
-Measure Objects
-Magnetize Objects
-Detect Ferrous Metals
-Wipe HDD Hard Drives
-Wipe Magnetic Strips 
-Play with cats
-and more...