An illustration of three characters: Volt is trying to push Amp through a narrow space being constricted by Ohm

I came across this nice cartoon online. There are many variations so I don't know who should really be credited, but I hadn't seen it before, and it's a good visual aid if you're trying to teach someone about the relationship between voltage, current and resistance. (Yes, some of the labels could be better, but it gives the general idea!)