Due for downloadable release next week (unfortunately, in Japan only), Rittai Kakushi e Attakoreda (which, via Tiny Cartridge, roughly translates to Hidden 3D Image: There It Is!) probably comes as close as anything we've seen so far to answering that long-burning question, "What're the cameras on the DSi really for?"
Augmented reality games haven't quite flourished, "print club" distractions don't hold much sway in the West — but achieving good Johnny Lee-style 3D by motion tracking via the DSi's front-mounted camera is something we can all get on board for, even if it's just for the simple paper-cut hidden object minigame Attakoreda offers.
Rittai Kakushi e Attakoreda is out next Wednesday, March 3rd — I'll update then with a report on just how well it works.