I like this hard rubber-coated case better than the skins I have seen. Also, I prefer a bit more thickness than the bare 8900 has. This gives protection and a better feel than the gel skins. And, it is very inexpensive...
BLACK RUBBER HARD COVER CASE for Blackberry Curve 8900 - eBay (item 390059818944 end time Sep-15-09 05:36:39 PDT)