Griffin Technology has released a new iPhone case, ClearBoost, which claims to boost the built-in antenna while providing physical protection for the phone. According to the support page…
“These improvements will, instead, translate into an increased ability to maintain connection with the cellular network, with more stations available to your phone, and less interference from signal reflections. This means fewer dropped calls, greater coverage areas, and faster Web browsing and file transfers.”
Personally, the antenna sticking up from the center of the case (what probably actually makes it work) is visually bad. Griffin has a great history of innovative products so perhaps the next version will find a way to shrink down the antenna and perhaps include a belt-clip of sorts.