If functionality is more important to you than looks, you might be interested in the newly-launched ClearBoost from Griffin.
This iPhone add-on boosts the signal on your iPhone via the built-in antenna, adding a screen protector and bump protection too. Ok, that ruins the sleek looks of your fashion-friendly handset – but it also keeps it in good condition, as well as adding those extra bars in low coverage bars.
No news on price as yet.
Griffin (via Engadget)