What is this invert?

[logan 12]

Does anyone know what this is? I found it in my tank crawling on the glass recently. I have never seen it before until now.

http://reefcentral.com/gallery/data/500/144693CIMG0945.JPG

 

[LeslieH]

That's a nudibranch, Tritoniopsis elegans. Beautiful but maybe not something you want in your tank since it eats soft corals like Lobophora.