With student Chang soo Lee's Cu.breaker concept you don't have to solve the puzzle, it does. This Rubik's Cube-esque device is a cell phone charger that 1) reflects rate and capacity of its device's charge and 2) shuts itself off with an automatic Rubik's twist when charging is complete to save stand-by power and prevent heat buildup and overcharging that can compromise your battery life*.
Cu.breaker's LED light patterns reflect the state of a plugged-in device's charging progress. Two lights glow at 10% charged, a few more at 50%, and all light up when you're juiced to 100%. Additionally, once the charge does hit 100%, Cu.breaker's circuit breaker feature kicks in, "breaking" the charger's top layer away from its base at a 45-degree angle. Power is cut, the phone is safe, and your outlet now looks like it has the greatest mind game of all time dangling from its prongs.
*Whether or not it's that big of a deal to keep a fully charged device plugged in is a topic of debate, with most in the know voting Nay, no big deal. Smartphone manufacturers have built-in precautions that stop the flow of current when charging is complete. Leaving a phone in its case, though, can cause overheating, which will compromise the battery. Read up on how best to protect and preserve your phone's battery here.