The ClearShield for iPhone 3G protects your iPhone with its translucent hard plastic, and it has ridges along the sides for grippiness. Two small silicone pads cushion the back of your phone against the inside of the case. All the buttons and ports are uncovered, and the opening for the dock port is fairly wide, and we were able to dock our iPhone 3G in most accessories without removing the case.
The big snag with these clear plastic cases tends to be how infuriating it is to remove one. On a scale of 1 to 10, with 1 being incredibly easy to remove even if you have no fingernails to speak of and/or you're drunk, and 10 being you basically need dynamite to get the case open, we score the ClearShield a 3. Just pry it open from the little plastic latch on the very top.
Links:
[1] http://www.maclife.com/user/sochs
[2] http://www.maclife.com/article/reviews/agent_18_clearshield_iphone_3g
[3] http://www.maclife.com/iphone3gcases
[4] http://www.maclife.com/article/reviews/iluv_icc74_clear_hard_case
[5] http://www.maclife.com/article/reviews/fommycom_nutouch_case_iphone_3g
[6] http://www.maclife.com/article/reviews/scosche_kickback
[7] http://www.agent18.com/scripts/prodview2.asp?idproductpages=36
[8] http://www.maclife.com/article/reviews/agent_18_ecoshield_iphone_3g