Professor Chi Nan of Shanghai's Fudan University has used a LED bulb to provide a high speed internet connection
Professor Nan explained that by using Li-Fi technology a light bulb with embedded microchips can produce data rates as fast as 150Mbps, much higher than the average broadband connection in China.
The term Li-Fi was coined by Harald Haas from the University of Edinburgh in the UK and refers to a type of visible light communication technology that delivers a networked, mobile, high-speed communication solution in a similar manner as WiFi.
Xinhua News article - http://news.xinhuanet.com/english/china/2013-10/17/c_132806591.htm
The problem with Li-Fi technology is getting the Internet to the bulb. It is understood all current Li-Fi systems make use of polluting Power Line Telecommunications (PLT) which can render the HF radio spectrum unusable.
UKQRM are a group that fights PLT interference - http://www.ukqrm.org.uk/