Ideas for creative portrait lenses?

I've been looking at getting a new lens and have really been enjoying a lot of portraiture. Realising this is the main style I would like to pursue, I thought a lens that would be suitable for this would be best, however, I wasn't just looking for an average lens as Ive already got a fairly decent one, I was thinking about some slightly more creative ones I suppose. I started thinking about this when I saw some of the lensbaby products which seemed to have a really nice effect for portraits and macro photography etc but I've heard mixed opinions when looking into it. Does anyone have any suggestions of a nice and quite versatile lens for a Nikon DSLR? Im not totally sure what I'm after so far so I'm open to suggestions. Thanks:D

Read more: Ideas for creative portrait lenses?