Konami is coming out with a stereoptic viewer adapter named ‘Solid Eye’ for use on your Play Station Portable. From the looks of the translated page it works on the same principal as a classic stereoscope (screen is divided down the center, each side has a slightly different view, and the brain fuses the image into 3D naturally) and works with Metal Gear Acid 2 (coming out in December for apx $50US).
Now I want a PSP so I can display my stereo slides in a cool high tech way.
Konami Introduces 3D PSP Viewer
Translated for your reading pleasure