I, too, have yet to see a cat get the better of a ferret!  The best
representation of this is, of course, a story!
 
SEVERAL years ago when I got my first ferret, I had this huge, male cat.
Not only was he huge, but he was also an excellent mouser (we live semi- in
the country).  Anyway, Fat Cat was inside sitting at the patio door when
Christmas first noticed him.  She immediately went to investigate.  My
father and I were watching from the living room and my dad mentioned
something about the ferret needing to watch out.  We moved closer so that in
the event that Fat Cat decided to do anything that we could stop it.
 
Christmas kept getting closer and closer until she was face to face with my
cat.  He was indignified by her noseiness and batted her on top of the head.
He didn't even waste his time with putting a claw out!  He began to turn
around and once again look out the door when Christmas bit his lower lip and
just went limp (you guys know how they do that).  The cat was terrified.  We
actually had to pry her off of him!  He thought twice before ever getting
near the ferret again!
 
Now, I have Pete and, until I moved recently, two cats.  The only one that I
think would ever have a chance at really hurting the ferret got her bluff in
on him a LONG time ago.  He may get close, but all she has to do is warn him
and he goes away.
 
Point of all this, your ferret can hold his/her own.  BUT watch out for your
cats!
 
cj & Pete
[Posted in FML issue 1352]