After Belkin's first attempt at a wireless HDMI system several years ago—which never got off the ground—the company is trying again with its new ScreenCast AV4. The system uses the 5GHz radio band and consists of a transmitter, shown here in the lower right, and a receiver (upper left) that can be up to 100 feet away in the same room. The transmitter has four HDMI inputs, which are selected with the included remote, and it can pass full-resolution 1080p and 3D signals. Available this fall, the list price is $249.