Bah!
The "tool" required is the human thumb.
I used to use this trick all the time when the cube-nerds appeared in-theatre (and they always would when the damned things first came out).
cn: "Go on. Scramble it. I bet I can solve it in <n> seconds".
yt: " Okay" (Turns back to sniggering of cube-nerd, scrambles cube as per request, gives nearest side a half twist to align middle tile with corner of layer below, pops out tile with thumb and rotates it 180 degrees before replacing it and scrambles some more before handing unsolvable cube back to owner)
And the fun was seeing how many seconds it would take before the cube-nerd would twig.