There was a mighty impressive video of Metal Gear Solid: Snake Eater 3D on 3DS at E3 2010. It showed a variety of viewpoints, 3D gimmicks, and fantastic graphics.

The video begins with a first-person perspective that shows the titular character, Naked Snake, walking through a jungle. There is a crocodile that gets very close to Snake and snaps its jaws. A log rolls at the screen, showing branches and twigs bounding towards you. For most of the video, you can use the 3DS slide pad to move the camera around, which at first is rather simplistic.

However, once you move onto the next viewpoint, which shows Snake in a third-person view, the camera begins to free up more. He crosses a bridge, and during this sequence, you can rotate around him. The parts of the bridge show up in front of him, and eventually you can see bees float towards Snake. It is a very nice effect, and it is kind of intense and foreboding as well.

It is unknown if this will be anything more than a tech demo, but it's still one of the most impressive videos shown on 3DS.