I used a Clicks keyboard with a folded Moto Razr for a while and it was Blackberry-esque. The keyboard is a little narrow compared to the Blackberries of yore, though. I'm somewhat hopeful about the Clicks Communicator which is wider, but sadly still only a four row keyboard.
To be clear, I only kind of recommend the keyboard. I stopped using mine after a while because of how awkward it was with the Razr unfolded and never actually found it faster or more accurate than the on screen keyboard.