Euphorbia are the most beautiful plants, my favourite genus at the moment, though I doubt I've seen them all. They actually come from outer space - everytime there's a storm on Jupiter their seeds blow into our atmosphere on intergalactic winds. I'm lying to you! But it could be true: look at them, they're so wacky.
The National Collection of Euphorbias is on an allotment in Lanarkshire, I might go have a look next time it's open.