VidiU streams over dual band MIMO WiFi, Ethernet, or via a single 3G/4G USB modem. For events that require you to be completely wireless, VidiU’s rechargeable Li-Ion battery lets you roam cable-free for up to 60 minutes.
It accepts HDMI video input and streams at resolutions up to 1080p. VidiU encodes video in real-time using H.264 compression and AAC audio at up to 5Mbps. Embedded HD audio, headphone output, and a mic/line input are supported.
Researchers at the University of Washington have developed AllSee the prototype of a hand gesture recognition system based on measuring changes in the ubiquitous electromagnetic field generated by wifi, tv stations, mobile phones etc. This allows for a low power gesture recognition solution that may even operate when integrated in a cell phone that you’ve put in your pocket.
On re:publica 2013 the Berlin based german data designers from OpenDataCity created a wifi tracking network with 100 Access Points that allowed them to visualize the movements of about 6,700 different electronic devices during the conference.
The application called re:log is a dynamic map of the conference location that shows the approximate locations of the devices when they were connected to the local WiFi hotspots. An interactive timeline underneath allows to explore the dynamic changes over time, while a rectangular area can be drawn to more specifically highlight and follow a smaller amount of dots.
The visualization was based on tracking the MAC addresses of the devices according to the WiFi hotspot they were connected to. This data, which can be downloaded, was fully anonymized, yet the authors mention their desire to allow people to look up their own MAC address in the future.
I suspect the solution used is based on MagicMap a free Wifi/Bluetooth tracking architecture developed at the Humboldt-University Berlin. Their Wiki has some more information.