Until a nice Rhinoskin slider type of case comes out I'm using the generic
Bodyglove Datasuit I got for my Visor Deluxe. Two 1/2" squares of velcro hold it in place well enough. It zips up all around the unit and provides at least as much protection as the Dell 'freebie' case but is much snugger so I can put my Axim in my coat's inside pocket.
I recall it being quite cheap and available at CompUSA and probably at Staples as well. :D
Ounce
(I'm keeping my Visor as a backup PDA, it currently sleeps in its Rhinoskin Titanium Slider case. (Yes, real titanium, I want one for my Axim.

))