Google is planning a massive expansion at Googleplex, its Mountain View, Calif., headquarters.

(Credit: Daniel Terdiman/CNET)

Google has big plans for Googleplex.

The company's Mountain View, Calif., headquarters will soon welcome a 120,000-square-foot "Google Experience Center" that will serve as a combination private museum and meeting area, according to a San Jose Mercury News report. The $120 million expansion will also reportedly house labs to test secret projects such as the company's "@home" project--rumored to be a home entertainment device.

The Google Experience Center would allow the Web giant "to share visionary ideas, and explore new ways of working" with up to 900 guests at a time, Google said in documents filed with the city of Mountain View and viewed by the newspaper.

"The Experience Center would not typically be open to the public--consisting of invited groups, and guests whose interests will be as vast as Google's range of products, and often confidential," Andrew Burnett, an architect working on the project, explained in a letter late last year to Mountain View officials. "Therefore, the Experience Center must also operate somewhat like a museum, exhibit, or mercantile space allowing flexibility in the exhibits so that as Google's products and needs change, the space can adapt."

A lab for a division referred to as "Google/@home" is designed to screen out radio frequency signals, allowing the company to test wireless consumer technology, a Google real estate official told Mountain View officials in a letter last year.

The Google/@home "RF screen room will be used to test the Wifi performance and development of a consumer product," Lewis Darrow said in the letter.

The company is working on a home entertainment device that would "stream music wirelessly throughout the home" and be marketed under Google's name, The Wall Street Journal reported last week.