Top-of-the-line coaster brake hub?

Is there such a thing as a top-of-the-line one-speed coaster brake hub? I'm thinking of (gasp) turning my fixed-gear into a free-wheel one-speed. I want a light and fast one-speed for commuting. Ideally I'd get another bike, but I think maybe I have enough. And though I have loved my fixed-gear, the Screamin' Salmon, since 1999, and though it's great going up hill, every time I go down the Queensboro bridge, I wish I could coast. That's the best part of the ride!

Plus, this would give me an excuse to build a set 650B wheels. Not only are 650Bs cool (if I say that enough, maybe I'll believe it), but they'll allow full fenders and this frame has always been just a little big for me. So an extra 1/2 inch of clearance.

The coaster brake would have two advantages: one, rain, two, I can put on an Egyptian spoke bike bell and avoid the problem of having to fix three hand brake levers. It's such a shame I now have this great bell on a bike I rarely take into Manhattan. Crossing 3rd, Lex, Madison, and Park... that's where I want to ring!