Hey, I've noticed that, too!  We have two cats and one ferret, Daxter.
He usually creeps up on them when they're napping, (they're grown cats)
and he gets real still and acts like he's wanting to nap along with
them.  I thought he was just trying to fit in at first and was charmed
by it..but no, eventually (and the cats have learned this) he tries to
stalk up on to the back of one of them and see if he can grab it by the
scruff of the neck.  They keep their eyes cracked open now whenever he
comes up on the chair to them, they're ready to swat and spit if he
tries anything.  Our female cat has starting just getting down and going
somewhere else (angrily, of course).  I just think Daxter wants to drag
them off and stuff them under the couch along with his sock stash!
Ha!... So, maybe it's a "bluff" so as either to be able to "hunt" them,
OR to keep from alarming the cats and getting themselves swatted?...
Your guess is as good as mine...
 
-Donna
[Posted in FML issue 3971]