The GBA game "
Yoshi Topsy-Turvy" features "
Tilt Control", so I'm guessing it includes a tilt sensor, whether it's roll-ball, or mercury tilt. I should be able to extract that sensor, and incorporate it into an internal tilt sensor, in the DS Lite. I will need two games though, but I think I could get the game pretty cheap on eBay... It would be much smaller than the homemade tilt sensors. Any one have any doubts this will work?
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Here is a game play video:
NAVGTR Ballot Video: Yoshi Topsy-Turvy