Three years ago, Rex Hammock set up a small website for the 25 employees in his Tennessee magazine publishing company.

On the site, he posted a daily selection of industry news snippets and articles, interspersed with personal comments and messages. It was a regularly-updated website, the kind now universally known as a "weblog" or "blog".

Mr Hammock soon realised that more people were reading www.rexblog.com than just his in-house artists and editors. "I discovered a small but loyal group of magazine geeks - as my 17-year-old daughter calls us - followed the blog.

"Whenever I attend any magazine industry functions, I usually have someone I don't know ask me if I'm the rexblog Rex. It's a bit strange."

Soon even stranger things started happening. Mr Hammock got invited to appear at more conferences and industry panels. More people went on to Hammock Publishing's website and read its press releases. One regular reader invited him to compete for a magazine contract and eventually handed him the business.

Rex Hammock had become one of a growing list of CEOs to discover the strange and persuasive power of the weblog.

When blogs first started appearing, they were largely the domain of tech-savvy diarists. They used the classic blog format of regular, dated entries to share the daily details of their personal lives alongside links to cool sites that they had just found online.

Today, they are slowly being joined by a much smarter set of corporate "bloggers" - CEOs, consultants, venture capitalists, analysts, other senior executives - many of whom, like Mr Hammock, discovered the power of blogging almost by accident.

Roland Piquepaille started writing his blog "Roland Piquepaille's Technology Trends" (http://radio.weblogs.com/0105910/) from Paris when he had some time on his hands after being "downsized" at SGI, the supercomputer company.

"I decided to write about how new technologies were modifying our lives, because there are almost always good and bad things coming from new or unproven technologies… At that time, in March 2002, I didn't have that many expectations. I thought that several people could read my blog and enjoy it."

Two months ago, his reader count broke through the three million mark, with more than 150,000 people logging on every month. When he started blogging, he found 50 references to his name on Google. Type in "Roland Piquepaille" today and you will get just short of 40,000.

The numbers are important for Mr Piquepaille because they have added up to a much bigger personal profile in his chosen field. It is a profile that he has been able to translate into a new business venture as a blogging consultant, helping companies set up their own blogs as platforms for their own executives or as tools for managing specific projects.

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