Comment London stock exchange crash (Score 1) 792
Statement on the cause of the crash mentioned "connectivity" which is consistent with the Infolect message passing system.
The Infolect system based on MS .Net and SQL server and HP proliant servers.
http://whitepapers.silicon.com/0,39024759,60237581p,00.htm
Infolect was also blamed for outage in November 2007
http://www.computerworlduk.com/technology/networking/messaging/news/index.cfm?newsid=6089
NYSE recently moved to Red Hat.