Wolfy mentioned Taz' wheels. I don't know if this still a good address,
but it worked for me, so here is the contact info for Lois Casselman,
who owned Taz and made the ferret wheelchairs and wheels. Also another
link.

Taz was the beloved ferret of Lois Caselman. He had a hind-end
paralysis. Lois' husband made a special wedge-shaped, three-wheeled
skateboard for Taz and he loved it! Taz would jump on his wheels and
take off across the floor. They now make Tazzie's Wheels for other
ferrets with the same problem. You can reach Lois at
xxxxxxxxxxxx
[Moderator's note: e-mail address removed since I don't have
permission to post. BIG]

Doggon' Wheels makes light-weight custom products for animals with
disabilities and can design a personal set of wheels for your ferret.
For additional information visit http://www.doggon.net/home.html
or call 1-888-7-DOGGON (888-736-4466) in the US and Canada
or 406-522-1510 outside the United States or Canada.

-- 
Renee Downs
"Eventually we will realize that if we destroy the ecosystem we
 destroy ourselves." Jonas Salk
"The most effective way to do it, is to do it." Amelia Earhart
It's amazing how much can be accomplished if nobody cares who gets
the credit!
Ferret Emergency Response, Rescue & Evacuation Team (F.E.R.R.E.T.)
http://www.ferretemergency.org

[Posted in FML 7291]