Ghostwire seems like an interesting title coming to the DSi.  No no, not the DS.  This baby’s a DSi exclusive, and it’s plain to see why in this game description on developer A Different Game’s blog:

Your portable device is used as a portal to the astral plane, and helps you find and collect ghosts that exist all around you. In your quest you use real tools, such as the built-in camera and microphone, as well as abstract ones like an “EMF tuner” for tracking down the ghosts. Once you find the spirits, you document them and find out why they haunt our world. They also give you riddles to solve. Ultimately, you will help them find peace.

The premise of the game seems really cool, and it’s a unique way to use the cameras of the DSi.  Checking out this teaser trailer might give you a better idea of how the game works:

Also, it seems that the game was being developed for cell phones as well, but I can’t tell if the developers stopped doing so or if it was released already.  Either way, this game is looking good for a DSi exclusive.  Now I’m just hoping for more DSi exclusives that’ll get me to save up for the system.