I have written before about Intel’s Cliffside project. This went public at CES in January under the name My Wi-Fi. The idea is to make your one laptop Wi-Fi adapter into two virtual adapters. One of these adapters is a regular laptop Wi-Fi adapter like before. The second turns your laptop into a kind of mini access point. Consumer electronics like Apple TVs and Wi-Fi printers can then stream media directly to and from the laptop, rather than relaying it through a real access point:
Realize first that, from an overall network topology standpoint, a single video stream coursing from source to destination is actually two streams; one going from the source to the router and through its integrated switch, and another heading out from the router to the destination. [Brian Dipert]
My Wi-Fi also allows Wi-Fi to substitute for Bluetooth for laptop wireless peripherals, like mice and keyboards, and this CNET article points out that it can also be used to share paid Wi-Fi connections in hotels and hot-spots.