I just wanted to add one little bit to this pastime.  I too swing my
ferrets in various bags as well as in my sweat pants and t-shirts.  One day
I found out that one of my little guys suffers from motion sickness.  He
can't take the swinging like the others can.  The day I found this out was
the day I found him foaming at the mouth.  It was mild and thankfully I
don't swing my ferrets in an aggressive manner.  Since then, I am very
careful with any repetitive movement that may make him sick to his stomach,
as well as take careful note of how the newcomers react to these types of
movements.
 
Betty and Her Blur O'Fur
[Posted in FML issue 2766]