It can do basically everything what the original one can do - except gaming (and the WiFi-connection doesn't work - in case that disappoints you).
Attention: This is not an easy model. I took care to keep important details, nerd-spoken it is not an Arcade-version, it is a Simulation-version.
The full PDF is downloadable at http://www.kamibox.de
Step 1: History
The Nintendo 3DS is the sequel generation of the Nintendo DS, released 6 years ago. The Nintendo DS itself is not a sequel to any generation, it came 5 years after the Game Boy Advance, but doesn't call itself a Game Boy.
As the Nintendo DS had 4 versions, the Nintendo DS Classic, Nintendo DS Lite, Nintendo DSi and Nintendo DSi XL, which all belonged to the same handheld-generation, it is inevitable that the 3DS will also have other versions, which may come in 1-2 years. The current design resembles that one of the Nintendo DS Lite, as shown in the comparison below.
The most innovative feature is the 3D-without-glasses effect on the top screen, the lower screen is touch-sensitive. Additionally to the original DS, it has a slide-pad, 2 outer cameras to take 3D-pictures and play AR-games, one inner camera, Street-Pass etc.
The papercraft model of the 3DS is already a few months old, but the design was minimally changed and so I had to edit the model a bit. I took all size details and pictures that had been released as references and I hope that it is very close to the original one.