Looks like 10 speed Thread on freewheels now exist! DNP is making them, 11-32 gear range.
Now showing at a few online stores but not in stock yet. Guessing this spring ('12)
being at the lighter end of the scale and having an old PhilWood hub that I can have the axel changed to 130mm on, I'm pretty thrilled. Will make a great extra wheelset for my winter bike.