1. Preceeds any noun that can perform an action, usually saving the day when it does. I.E. Go Go Gadget Can Opener - what you say before opening a can of tunafish for someone. Or: Go Go Gadget Shower - what you say before spraying someone with a garden hose.
2. Also you can say it to make fun of someone who makes it a point to always be the "handy" one in the group - carries a pocketknife for example - and offers help as if they have been hoping to all day.
"Go Go Gadget bottle opener!" (procures opener from pocket)
(or) "Go Go Gadget tabletop" (opens beer on table edge)
2. "I think my wallett fell under the table. I can't see."
"here, use my flashlight" (pulls flashlight from pocket)
(sarcastically) "well, Go Go Gadget flashlight"