The mobility of stand-up paddle boards isn't typically that great, they are just too long for most people to transport them easily. Unless you have the modular Rum Runner SUP or the inflatable SUP from Current Drives.
The inflatable stand-up paddle board from Current Drives has some cool features that make it one of our favorites. You get a stand-up paddle board and paddle that fit in a large backpack. And you can add on their electric motor system, the ElectraFin. The ElectraFin system slides on to the existing fin-box and comes with an electric motor/propeller, a lithium power pack, and a wireless remote control you wear on your wrist.
Perfect for light paddling, upstream paddling, small cars, bikes, fishing, as a dinghy support boat, etc, The entire system is about $1,600 here. Video of this awesome setup after the break.