Lucid now sees an advantage for this technology because of the Thunderbolt interface and often underpowered Ultrabooks that may have enthusiasts wanting more in the graphics department. Their external box integrates an AMD Radeon 6700 chip, which has the potential to improve the graphics performance of a base Ultrabook by a substantial margin.
So, is this technology coming to market? It is a concept right now and far from being a market-ready product. As passionate as we were about external graphics in 2006, it is still much more likely that external graphics would be, if commercially sold, a niche product and not a mainstream solution.
Source: Toms Hardware