Google nears $600

Shares of Google opened up 10% Friday morning, and came within striking distance of $600 for the first time in more than nine months, after the company posted solid quarterly earnings that impressed investors.

Google's (GOOG, Fortune 500) stock rose as much as $58.42 to $599.35 a share in early morning trading, before sliding back a bit. It was the stock's highest level since January.

Late Thursday, Google reported a third-quarter profit that rose 32% on the back of stronger search ad fees from advertisers. But the company's results were also buoyed by its non-core businesses, like YouTube, display advertising and mobile.

Google defied skeptical investors and analysts who feared that the search giant would never find a a significant new revenue stream besides search advertisements. In the past, the company has been tight-lipped about the financial details of its non-search businesses, leading some analysts to speculate that those product lines were insignificant to the company's overall revenue.

For instance, Google has made tremendous headway in mobile. Its Android operating system will command 17.7% of the global mobile device market by year's end, according to a Gartner forecast, making it the second best-selling smartphone operating system, behind Nokia's (NOK) Symbian OS and ahead of Apple's (AAPL, Fortune 500) iOS. That's stunning, considering it entered the market just two years ago.

Google said its mobile advertising business was doing sales of $1 billion on an annualized basis. Display advertising, which includes images rather than textual ads, is on pace to be a $2.5 billion business annually. The company said its display business is likely the third largest in the world, behind AOL (AOL) and Yahoo (YHOO, Fortune 500).

Investors had slammed Google's stock this year, sending it down by as much as 30%. Shares started to rebound in September, but were still down 13% before Friday's market open. But Google's impressive quarterly numbers sent shares soaring, and the stock is now down just 4% for the year.