If you read this blog, you will probably find this interesting: InformationWeek > Data Demands Respect.

"We do three things really well," says Alex Dietz, who's referred to internally as "products and infrastructure technology leader" and functions as Acxiom's CIO (there are no traditional titles in the company). Those three things, Dietz says, are managing large volumes of data; cleaning, transforming, and enhancing that data; and distilling business intelligence from the data to drive smart decisions. That data is used by Acxiom's approximately 1,000 clients for everything from developing telemarketing lists and identifying prospects for credit-card offers to screening prospective employees and detecting fraudulent financial transactions.

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No one at Acxiom seems to know exactly how much data the company manages in its 11 tightly guarded data centers. The company's central data center is located north of Little Rock, in Conway, Ark., where Acxiom was founded in 1969 as a spin-off of a local bus manufacturer. Acxiom also has data centers in Downer's Grove, Ill., outside of Chicago, and as far away as Sunderland in the United Kingdom. The company recently opened a data center in Phoenix, and an additional facility is under construction in West Little Rock. The best estimates are that the Conway systems alone store between 1.5 and 2.0 petabytes of data, or up to 2,000 terabytes.

Acxiom just passed a billion dollars in revenue for the first time last year.