Saw a Superduke the other day didn't have a hugger on, but had some kind of foam surround on the shock, looked like a massive air filter. Found these ones for ATVs which look similar http://www.nextag.com/atv-shock-covers/compare-html
Didn't look too bad as it goes, would probably still look naff after a couple of days in the wet though, but should keep the worst off the shock