Multi-Touch Interaction Research
This Multi-Touch video demonstration shows how a touch screen could handle multiple contact points simultaneously and how it would allow the user to interact with things. The video shows drawing programs, image and interface resizing, Google Map-like navigation and even multiplayer games.
While touch sensing is commonplace for single points of contact, multi-touch sensing enables a user to interact with a system with more than one finger at a time, as in chording and bi-manual operations. Such sensing devices are inherently also able to accommodate multiple users simultaneously, which is especially useful for larger interaction scenarios such as interactive walls and tabletops.
I can't see this sort of thing being widely implemented in PCs, but it does show some interesting applications. Think of this as a mix between the Nintendo DS and a PC.
Link (via Waxy)