I also use the soda bottles by cutting off the ends, slicing them end to
end so I can adjust how big the opening is and sticking them INSIDE clothes
dryer vent hose.  I don't know about other ferrets, but mine won't play in
the hoses because they collapse over time.  This way they stay open and
make great runways.  The veasels zip, zip, zip through them!  I also tape
them together to make tunnels and ramps to all the cardboard boxes for
playing in.
 
Carla Roberts
ADSA, AL President
http://www.skunks.org/Home.htm
[Posted in FML issue 3498]