Makey Makey Go is a super-cheap invention kit. For $19, you get a USB stick and an alligator clip; use the two in tandem and you can turn (almost) anything into a keyboard or mouse button. Examples of potential uses include a Slip'N Slide that takes a photo as you zoom past, a donut spacebar, a dog bed that initiates a Skype call and a foil sword game that counts the number of times you hit an opponent. If you have an idea that requires more than one button, you just plug in another stick.
The Go is a lot like the original Makey Makey (now known as the "Classic" edition), which works on the same principle but lets you hook up multiple alligator clips and also includes an Arduino for more advanced hackery. "We redesigned Makey Makey Classic to focus it down to its absolute bare essentials," its inventors explain, "to feel more like a kitchen gadget or a multi-tool and less like a traditional circuit." Like the original, Makey Makey Go is relying on crowdfunding to move into production, with its creators seeking $10,000 through Kickstarter. They've already sold 200,000 Makey Makey Classic Kits, so it's a safe assumption that the Go will be hitting its target pretty soon.