Anything apart from the two mainstream default harmonicas (Solo-tuned fully-valved chromatic, and un-valved Richter 10-hole diatonic). Alternate tunings, different construction, new functionality, interesting old designs, wishful-thinking... whatever!
May your holidays be nice and harmonic! (poor pun intended )
Edit: It just occurred to me that for most people Christmas is not until tomorrow! Anyway, in Sweden the big day is today, so I'll keep the post.
And for all the swedes: GOD JUL!