There is always news about Vehicle To GRID. Below are some links. Let us know if you know of others as this feature grows. There are units and options being used on Vehicles all over the World. It just seems in the USA it is not available from more than the original Company that has lead the way ACPropulsion. They have bi-directional power available in all of their Electric Vehicle controllers like the famous T-Zero , MINI E (BMW mini made Electric)  and eBox (SCION xBox made Electric) cars. The real life example and testing now going on at the Univ. of Delaware is using over a dozen eBox and MINI-E vehicles.

Note 500 Mini E vehicles were modified for BMW and only Leased for 2 years . They were then taken back and BWM makes their own Electrics like the Active-E , i3 and soon the i8.
http://en.wikipedia.org/wiki/AC_Propulsion_eBox
http://www.acpropulsion.com/products-v2g.html

Also both Nissan with the LEAF and Mitsubishi have a unit that plugs into their Fast Charge Port and can do V2H Vehicle to Home /GRID/Business. It has been tested in Canada and Japan.
http://blog.powerstream.ca/2012/06/nissan-canada-showcase-innovative-power-supply-technology/
http://www.myelifenow.com/2012/05/nissan-launched-leaf-to-home-v2h-ev.html

Recent more Articles on V2G-101:
 
To view the complete article, click the appropriate date link. More stories are on the web everyday.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2009-04 - My Ride- It’s A Power Plant.doc

2013 - Home now has a V2G option   http://www.greenfleetmagazine.com/news/51818/honda-joins-v2g-technology-project
 
2013 - http://evworld.com/news.cfm?newsid=32007 
Nissan Uses LEAF Electric Car to Light Holiday Season

2013- La Times article on V2G 
Electric cars may hold solution for power storage