If you're clinging to your BlackBerry because of physical keyboard, you just lost your last excuse: this TK-421 iPhone 4 case includes a physical keyboard that flips out whenever you need some thumb-tapping typing action.
The keyboard case from ThinkGeek—also available for iPhone 3GS—connects to your phone via Bluetooth and is compatible with its email, browsing, notes, and calendar apps. When you flip your phone out, it's supported by the hinge, so all you need to do is hold on to the keyboard and type away in portrait mode like so:
All apologies to 3G owners, but without Bluetooth support this becomes nothing more than chunky accessory. For those who've upgraded iOS phones in the last couple of years, though, you can pick up the TK-421 for $50 starting in late November. [ThinkGeek via ChipChick]