Ok, this idea is a little out there... I've seen a few mentions of having a four dimensional game. The problem is that there is no way to actually display more than three dimensions. With two screens on the DS though you could have one view of XYZ and one of YZW (or any other combination), and suddenly everything works out. It would definitely be...mind boggling [wow]. An action game would probably be out of the question, but I can envision an incredibly challenging puzzle or maze game. There's no reason this has to be on the DS, but most PC/console gamers don't really like split screens. The DS is just crying for someone to do something other than a map with that second screen. Thoughts?

to be honest, i think that's the biggest problem with the DS. no one knows what to do with the second screen. maps: well that's ok, but not innovative. menu screen: ditto. inventory list: ditto. radar: ditto.

what can you do with that second screen to make gamers say "wow!"?

You can watch a porno movie on the other screen.... "utilize the touch screen"
You could also do multi-game viewing type thing... i'm walking in 1st person but the top is in 3rd person what for.... think MG.

the problem that strikes me is the following:
You can't use them both at the same time. Period.

First, it's hard to focus on two screens at the same time. But not impossible.
Second, it's impossible to hold the gameboy correctly and at the same time hold a pen on the touch screen. Unless you use your mouth.

How do you even use the touch screen without having to let go of the buttons with one hand? DS is not asking so much what innovative games you can do with two screens, but as what innovative moves you can do with two hands trying to do three things ;P

My 0.02 swedish crowns.

EDIT: to be nice to the OP; in a racing game the lower screen could be the rear view mirror...

EDIT2: actually I think I found a way to hold all three things, but I think it will hurt. Unless you're a yoga expert.

Yes! John Madden's Tellustrator 2006!

I like the system where Metroid uses it as an analog control interface while the top screen is for play.

Anything that you use the GameBoy Advance for in a GameCube title would be okay, like the WInd Waker Tingle Tuner. Whatever it is, it should use the touch screen. I would like to see a Rainbow Six-style waypoint and order system on the lower screen. Put a mini-map on it in an RTS-type game and use that to issue move, attack or formation orders with the stylus.

Yes, I also think that some portable RTSs could prove to be the "killer app" for the DS. I know they were looking for innovation, but RTSs are games that are just begging to be ported to that touch-screen.

shmoove

I liked those ideas too. But what would you use the controlls and upper screen for? Otherwise those are just Palm games :)

The d-pad could scroll the touch-map (no mouse scroll with a touch-screen), and the the L-Button could switch cursor modes (hold it to select units, release it to command them). The other buttons could be for map or unit hotkeys, or be linked to special abilities (stimpack, cloak, etc. in StarCraft parlance).

Actually; it's rather easy to use the touch pad without the stylus. The system comes with a little thumb nubbin thing on the strap.

Yeah, for action games (i.e. Metroid Hunters) the thumb knob is actually the prefered method.