Take a look at GRResearch NX Open Baffle Speakers. Great sound, excellent detail at low volumes, and rock as hard as you can stand it.
Tekton Open Baffle Speakers
I see they have new open baffle speakers with 15 inch woofers that can be pre-ordered for 3000 bucks. After the pre-order period they will be 7K.
Has anyone heard a prototype of this speaker? At this price point it's tempting to order and sell if I don't like it. I have 4 two channel systems and a vibrant stereo kit graveyard.