A nicely designed power adapter
Travel away & never worry about power adapters ever again!
There is no plug this little baby cannot master. Little light lets you know it's working before you plug in your expensive electronics. Note it's not a transformer. So make sure the thing you're plugging in can handle the local voltage. These days, most devices with power bricks (laptops, cell phones, etc) can handle anything from 110-220 volts, but check to be sure.