Acer has announced plans to produce a netbook running Google's Android as its operating system.
The Aspire One will come with a 10in screen and will be available later in the year, most likely in the third quarter.
Android was designed for mobile phones, but netbook manufacturers like China's Guangzhou Skytone Transmission Technologies have already begun using the operating system in netbooks.
Acer refused to give any details on pricing, other than to say that the new netbook would be less expensive than models running Windows. Microsoft usually charges around $20 (£12) per licence for its netbook operating systems.
Acer said that it will continue to offer netbooks powered by Windows, and recently launched a joint marketing campaign with Microsoft to promote Windows on netbooks.
Android might not be the only thing worrying Microsoft at the moment. Oracle chief executive Larry Ellison said at the JavaOne conference that Oracle and Sun could be getting into the netbook market too.
"You will see us get very aggressive with Java, and develop Java applications for phones and netbooks," he said. "I don't see why some of those devices shouldn't come from Sun. There will be computers that are fundamentally based on Java."
Microsoft has angered some in the netbook manufacturing sector with new terms and conditions for Windows 7, stating that it will not allow the netbook version of its new operating system on devices with a screen size larger than 10in.
Use the same password for every website? It might be time to change them all
Applicants for parking bay suspensions put at risk of credit card fraud by Islington Council
Robert Swan appointed interim CEO after Brian Krzanich's departure
Should you link your data sets to add value, or leave them separate to reduce risk?