Google's search for new ways to make money continued Monday with the announcement that it would pay $625 million in cash to acquire Postini, a San Carlos company that provides e-mail security software over the Internet.

Analysts said the deal, which is expected to close this fall, could bolster Google's credibility with businesses as it ramps up efforts to sell a suite of online software tools known as "Google Apps" that handle e-mail, word processing, calendars and spreadsheets. Google and Postini executives said the move underscored... more on Google's buyout