My 3DS messes with my eyes. I don't know if it's just me, but the 3DS and viewing anaglyphs makes my vision wonky. If I look at anaglyphs through red/cyan filters for a while (such as playing WoW in 3D), then everything I look at has a red or blue tint for a while. After playing my 3DS for a bit, I swear I can discern each eye's input for the rest of the day. Like, yeah... it's weird and kinda annoying. It goes back to normal after some sleep, though. Then there's some weird visual effect that objects moving left-to-right seem closer and objects moving right-to-left seem farther. Or something like that. I almost got hit by a bus once because I thought I had time to run across the street but it was closer than it looked.