Small businesses don't always need Microsoft Office software for word processing, spreadsheets, email, database and publishing tools.
Buyers of computers running Windows RT, the Windows 8 version for ARM-based devices, will receive at no additional cost a version of Office.
Office 365 celebrated its first birthday in July, and the cloud service has attracted an impressive list of educational customers over the last year.
InstallFree Nexus is an intriguing option for Word lovers who crave Office via the Web or on an iPad.
Microsoft hopes that new features built into the web-based Outlook client will draw web users away from competing services like Gmail and Yahoo.
Microsoft must aggressively price its Office 365 subscription plans, perhaps as low as $2 a month, to convince consumers that it's good to rent software.
UPDATE: A refresh of the 2-year-old Office Web Apps suite, a rival to Google Docs, is available for testing.
Windows users will get five licenses to Office 2013 in new subscription plans, but Mac owners must purchase Office separately.