Whilst typing 'whilst' I came up with another nerdy toy, I was going for "Name that Angstrom" with the contestants getting a 1/5th of a second flash of the light (keeping it within the visible light range just to be sporting), then each team get three guesses.
The original idea was "Name that Atom",
with the aid of box with a hand-sized hole in it, and one of them things which is like lots of rods, going through a block, which when pressed onto something 3d reproduces the shape (a pin-board?). This could work in one of two ways.
The first way, is just kind of lazy, just connect the pin-board to an atomic force microscope.
The most satisfying way would be the to have an array of pin-boards, each one having the rods getting smaller and closer together until the final pin-board gets to the sub-atomic level. Obvious problems would backlash in the gear train, but where there's a will etc.
Can't you picture it, the first contestant steps up to the plate, inserts hand and goes..." hmmm...2, 8, 18, 9, is that 2 electrons...err, err, err it's Yttrium isn't it?" and compère asks "Final answer?"....