Check out this review of the SPE Slider case in black rubber. I think I like the SPE case better than the 2-piece Seidio case that I have now. From time to time, the Seidio case pops open on either side (but the case still remains together). Also a drop splits the case totally open where the SPE Slider is one piece.

The end of the review mentions that a 750 version should be out soon. Hopefully, they make a wratchet type clip for the case so it can be worn vertically or horizontally. If they make that type of clip, I am definately going to pick up this case. It does look really slim and adds little bulk to the Treo, unlike the Vaja case (heh with non-centered clip attachment).