Credit: jake krol/mashable While Alpha Training Blue is not a perfect toy, it's pretty darn close. At $249, it's a little pricey, but you're getting a pretty sophisticated robot that impresses ...

A capped 2-liter plastic bottle containing a clear, colorless liquid is shaken. The liquid turns a deep blue color. At rest, the liquid returns to colorless. The cycle can be repeated many times. Ask ...