Here's some Dinophysis, a group of dinos with rather interesting morphologies. (though the top left and the very bottom left aren't part of this group, as far as I know) I've first come across these in Haeckel's drawings, and thought he was making this stuff up. Apparently, there really are organisms vaguely shaped like whirling teapots:
(Source: Waller Lab); main page here (with more pretty pictures)
Also, these have undergone a tertiary endosymbiosis event with a cryptomonad. As cool as they are, they're fairly understudied as some have only been cultured fairly recently. Even more interesting morphogenesis questions there...
And shit, someone just timetravelled forwards and 'scooped' my ideas. People (zoologists+botanists) usually give me funny looks when I say cell differentiation in multicellular organisms is but a spatial version of developmental stage differentiation in unicellular ones... but I'm not alone! =D
Must be a Russian thing. Привет, братья! ^_^