The Fifth Element
Mondoshawan ship
dir. Luc Besson

I'm not sure if this ship is the work of Moebius, Jean-Claude Mezieres, +Sylvain Despretz, or someone else, but to me it's always been a pinnacle example of sci-fi "biodesign" done right, whereas most is horrible. What makes the achievement remarkable is how fine the line between good and bad is when it comes to this look/style. I saw a film last summer that was chock full of remarkably similar designs, but it all looked completely silly and left no lasting impression. There was no depth.