I am test riding a dingle-6 geared bike today. AW hub with both 28T and 18T in the back (spacers removed) with 52T and 42T double crankset. Gives crazy wide range, but requires a 15mm wrench to change between 42x28 or 52x18. Gear range is from below 30GI to over 100GI. I followed Sheldon's suggestion of making the larger 28T sprocket for the AW hub by grinding some of the teeth off sprockets from an 8 speed cassette. I will report on my test once I have ridden for a few days.

-Will