London Stock Exchange dumps Windows for Linux:

When it comes to business computer systems, nothing is more mission-critical than the massive trading software systems that underlie stock markets. A failure of an hour here can mean billions of dollars of lost trades. The LSE (London Stock Exchange) learned that the hard way when their .NET/Windows Server 2003 trading platform died like a dog early last September. The new LSE management is not going make that mistake again. This October, the LSE purchased MillenniumIT and will be switching its stock exchange programs to the company’s Linux-based Millennium Exchange software.