[greatmaul]

I've never seen any other tanks available for the GZ, although I think it would be awesome.

I looked for such a thing once and the only thing I came across that was close was a thread where a guy took 2 tanks for a Ninja250 and combined them to make a tall tank. Sounds like way too much work for such a fuel efficient bike.

I think for hardcore adventure riders they have "extra" tanks that you can plumb together with your main tank, but that's also probably too much work unless your life depended on that extra fuel.