I'm not sure if this was on here before, but I couldn't find it in the tags:
"Elysia chlorotica is a lurid green sea slug, with a gelatinous leaf-shaped body, that lives along the Atlantic seaboard of the US. What sets it apart from most other sea slugs is its ability to run on solar power."
http://www.newscientist.com/article/dn16124-solarpowered-sea-slug-harnesses-stolen-plant-genes-.html http://evolutionarynovelty.blogspot.com/2008/11/evolutionary-novelty-photosynthetic.html