Play with the impressive power of green science with this fully equipped kit. It includes a digital clock, wires, prongs and assembly instructions. All you need is a couple of potatoes ...

Play with the impressive power of green science with this fully equipped kit. It includes a digital clock, wires, prongs and assembly instructions. All you need is a couple of ...

Play with the impressive power of green science with this fully equipped kit. It includes a digital clock, wires, prongs and assembly instructions. All you need is a couple of potatoes. $19.95 at ...

Play with the impressive power of green science with this fully equipped kit. It includes a digital clock, wires, prongs and assembly instructions. All you need is a couple of potatoes. $19.95 at ...

Would-be Kickstarter backers have two versions of the Levitating Nixie Clock to choose from. For starters, there’s a five-tube Relay version, which looks a bit like a floating test tube rack.

Play with the impressive power of green science with this fully equipped kit. It includes a digital clock, wires, prongs and assembly instructions. All you need is a couple of potatoes. $19.95 at ...

The clock in question comes from somewhere in the middle, around 1996. On the outside, it seems like any spaceship gizmo, and the digital clock keeps local time along with a stopwatch and an alarm ...

Similarly, push the key on another clock, and you'll only get a momentary glance at an animated hour hand. In order to keep track of time, visitors have to continually interact with the clocks.