NEW YORK (FORTUNE Magazine) - CEO Steve Ballmer is wrestling with Microsoft's perpetual problem: extending its near-total dominance of operating systems into the Internet era.

Google owns the Net: The search titan already offers several Web-based programs, allowing users to do everything from send digital photos to create Weblogs -- all without applications from Microsoft.

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And the software giant's effort to become the core of the digital home faces fierce competition at every turn, from Apple, Sony, Samsung, and others.

Microsoft is launching "live" versions of the company's Windows operating system and Office software that are transmitted over the Internet, not stored on a PC. Assuming these products are designed well -- and quickly -- Microsoft could dramatically expand its business.

Videogame machines, high-end servers, and other tech goods also offer moneymaking opportunities.

Microsoft (Research) is rolling out a slew of new products this year, including the latest upgrades of Windows and Office. And those franchises are still huge cash machines.

But Microsoft no longer deserves the rich premium it once enjoyed. At 20 times trailing earnings, the stock is priced about right.