Yes Vaseline is a safe and effective hairball remedy.  In fact, Vaseline is
just a trade name for petroleum jelly, which is the active ingredient in
most commercial hairball preparations!
 
I use Vaseline with a little ferretvite for flavor for our ferrets.  They
love it, in spite of the goopiness that gets stuck on their whiskers!
 
Linda Iroff
[Posted in FML issue 2600]