Sony has introduced the LocationPorter, a realtime video streamer that streams footage from a connected camcorder or camera across whatever connection you have available, to a second remote LocationPorter device. The device uses the internet via a LAN or 3G connection.
The streamer can combine both connections to support up to a 352 x 240 64fps video at 320kbps. A single 3G card can give you a video of the same resolution, at between 5 and 15fps with bitrates from 64 to 160kbps. When connected to a LAN, the video can be streamed up to 30fps at 1024kbps max. No word on pricing and availability yet.