Mains wall sockets with built in USB chargers
These days it is pretty universal that mobile phones and tablet computers recharge their batteries via their USB socket.
Some mobiles and tablets come with USB mains chargers, others don’t and just assume you already have one. Either way you can be scrabbling around trying to find a mains charger when you need one, or you plug your phone into a USB port on your computer and curse the fact it charges far more slowly this way than straight from the mains.
One elegant solution is to replace one of the double mains sockets in your home or place of work with one with a USB charger built in, that way you always know where there is a USB charger when you need one.
These 2 Way UK power socket plates with 2 USB charging ports have become quite widely available and are simply swapped in the place of an existing double gang mains socket by a competent qualified person.