There's a fictional piece about Neandertals in the journal Nature. You can access a little bit of it by going to the John Hawks blog for a sample. Otherwise, you have to pay $32 for it. Ouch! It apparently kind of suggests that there have been genetic exchanges between Neandertals and "moderns" from time to time, whoever and whatever Neandertals may have been(human, I should think).
In any case, I'm glad I'm pretty much suggesting the same thing, in an easy-to-swallow, fantasy/science fiction/romantic setting in my Great Medieval Science Fiction Masterpiece With Neandertals. Just think, by the time it's written, you should get a whole book for that price! Not just a measly story in a scientific journal!