At some point I'm going to make time to go out and explore some rockpools here to show you some of the amazing marine life the shallow temperate seas of the atlantic has. Until I get to that here's a taster/teaser of what will eventually come.
This is a snakelocks anemone, Anemonia viridis, a predatory anemone from the shallows. This one photosynthesises through symbiotic algae but it also has a bit of a zing to it. It can be kept pretty easily in marine aquaria (though not as easily as the beadlet anemone that lives alongside it). There are even reports of people persuading clownfish to inhabit these bad boys. Possibly then most interesting thing I can tell you about these is something I learned watching one of Hugh Fearnley-Whittingstall's River Cottage show, people eat them, considering them a delicacy. As wikipedia notes:
This anemone is consumed in southwestern Spain, around Gulf of Cádiz region, under the name "ortiguillas de mar" (literally, little sea nettles, because of their urticant properties before cooked) or simply "ortiguillas". The whole animal is marinated in vinegar, then it is coated in a tempura-like batter and deep-fried in olive oil. Ortiguillas are offered in some coastal Andalusian restaurants as a delicacy. They are similar in appearance and texture to croquettes, but having an intense seafood taste.