Here:

http://tingilinde.typepad.com/starstuff/2006/12/ferret_wheelcha.html#comment-26428316

and here is one with a ferret using it:

http://www.ferretfarm.org/index.html?target=dept_98.html&lang=en-us

It cost us $50 and is worth it.

Wonderful workmanship and good on carpet as well as hard flooring.

Right now we don't have one in need, but having been there and having
to wait we decided to get this one to have around simply because we
were already so impressed by it.

Sukie (not a vet)
Current FHL address:
http://groups.yahoo.com/group/ferrethealth
People can join there or can send a blank mail to the automated
joining address:
[log in to unmask]
and then follow the directions.
(The second is recommended for those having problems with Yahoogroups
web settings, and afterward send a blank mail from your subscribed
address to
[log in to unmask]
to get the digest instead of individual mails. )
Recommended ferret health links:
http://pets.groups.yahoo.com/group/ferrethealth/
http://ferrethealth.org/archive/
http://www.afip.org/ferrets/index.html
http://www.miamiferret.org/fhc/
http://www.ferretcongress.org/

[Posted in FML 5454]