ChiefMonkeyGrinder writes "This summer, the London Stock Exchange decided to move away from its Microsoft .Net-based trading platform, TradElect. Instead, they'll be using the GNU/Linux-based MillenniumIT system. The switch is a pretty savage indictment of the costs of a complex .Net system. The GNU/Linux-based software is also faster, and offers several other major benefits. The details provide some fascinating insights into the world of very high performance — and very expensive — enterprise systems. ... [R]ather than being just any old deal that Microsoft happened to lose, this really is something of a total rout, and in an extremely demanding and high-profile sector. Enterprise wins for GNU/Linux don't come much better than this."