The main odor given off by gliders is the usual waste smell, 
but it's not strong at all and if their cage is kept clean, you will 
never smell anything.  I should mention here, however, that the 
males do give off an odor before mating.  While not really bad,
it is a distinct odor, and may take over a room for a week or two.
Gliders are very dependent upon their excellent senses of smell to 
identify other gliders, as well as their owners.

Male gliders have two scent glands which they use for marking -- 
one is located on their belly and the other on the top of their head
(which accounts for the bald spot).  When males grow accustomed to 
their surroundings, they will mark objects by rubbing their bellies back
and forth upon the object.  They will also mark any females in their 
colony by rubbing the female's chin with their head.