With all the gadgets that we carry with us today, its hard to imagine traveling without a charger. And when we do see a power outlet, we're quick to use it without even considering what sort of surge it might possibly have. Luckily, there's Satechi's compact USB surge protector.
The plug will connect both a standard power and a USB cable and protects multiple devices from electrical spikes and surges. If the LED light glows, it means its ok to plug your gear in but when its off it means its protection circuitry has been compromised by a spike and its not safe to use.
Pretty useful actually. More information on the plug at the source link below.