I have a huge cage that is also not about to head outdoors into the snow
to get a thorough cleaning yet- My two are "mostly" litter trained.  In
the areas they like to go outside the litter box I bought those cloth
pads that are made for baby beds that are absorbant.  I've had to weigh
them down so they dont float around the cage- but they seem to work
pretty well, theferretstore.com also sells disposable pads that work
as well.
[Posted in FML issue 4040]