In my opinion one of the weirdest HP pairings anyone could think of....
But that's probably the reason why I've grown to like the idea of the two of them.

They are both loony in some way. And I would like to see, for instance, some fanfiction about them. I think Loony Luna could be a perfect match for the evil and mad Barty Crouch Junior (plus he's being portrayed in the film adaption by David Tennant which is a big plus as well).