Does it surprise you that Linux has become the the most widely used operating system at big Wall Street firms? It might surprise some at first glance, but considering all the problems Sun Microsystems has had and the cost of Solaris, it's not surprising at all. Linux, after all, is as close to a free operating system as you're going to find. Wall Street firms also have the technical resources to customize and extend as they see fit, which adds up to a winning product.

According to Securities Industry News, quoting a Tabb Group presentation, Linux has displaced the Solaris as the operating system of choice by a wide margin. Nearly 70 percent of bulge bracket firms now use Linux, compared to 23 percent for Solaris and 7 percent for Windows. Linux is also popular with second tier broker dealers. Among very small companies, Windows remains popular.

I can't see the situation changing any time soon. Oracle will be hard pressed to do anything significant with Solaris, and Microsoft has always been challenged to show that Windows is an enterprise beast. But it will likely continue to carve out space at the low end.  

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