Probably the best press release written by Google was on April 1st 2004, when Google launched Gmail.

MOUNTAIN VIEW, Calif. - April 1, 2004 UTC - Amidst rampant media speculation, Google Inc. today announced it is testing a preview release of Gmail – a free search-based webmail service with a storage capacity of up to eight billion bits of information, the equivalent of 500,000 pages of email. Per user.

The inspiration for Gmail came from a Google user complaining about the poor quality of existing email services, recalled Larry Page, Google co-founder and president, Products. "She kvetched about spending all her time filing messages or trying to find them," Page said. "And when she's not doing that, she has to delete email like crazy to stay under the obligatory four megabyte limit. So she asked, 'Can't you people fix this?'"

Launching a product on April 1st had its risks (most people thought it was a hoax) and its advantages (the hoax turned out to be a real mail service, so real that some wanted to pay to get a Gmail address), but it was an excellent viral marketing. From CNN Money:

Google's one gigabyte of storage claim led to some speculation about the Gmail announcement being a hoax since it took place on April Fool's Day. Google has pulled April Fool's jokes on the tech community before, including jokes about pigeons being the driving force behind Google's search technology and that Google was looking to start a new research center on the moon.

In addition, the press release about Gmail was fairly goofy(...). But Jonathan Rosenberg, vice president of the products group at Google, said the Gmail announcement was legitimate. He did concede that the company did get caught up in the spirit of April Fool's Day in its press release.

Google made fun of its search technology, the contextual ad system, their work environment and products. What do you think they'll do this year? </img> </img> </img>