The second slide out screen can be used for a keyboard, coverflow, video playlist, thumbnail index, etc.
Brzezinski has even designed the packaging for the device.
Unfortunately, the image details are not in english. A translation was originally provided here but it seems the site has gone down.
Take a look at the images below or hit the link for the entire gallery. This is definitely one of the best concepts we've seen thus far.
Read More [via TUAW]