Norway-based Opera Software is gaining ground on Microsoft and AOL in the European browser market, research shows.

The company's browser, Opera, has seen the company's market-share more than double this year, Internet market-research firm WebSideStory has revealed. As of November 29, Opera held 0.67 per cent of the market - up from 0.3 per cent on January 1.

Growth was even more dramatic in Russia, where it has increased from about 1.5 per cent to 5.88 per cent. In Germany, Opera's market share grew from 1.3 per cent to 3.37 per cent, while in Sweden the company's share more than tripled, from 0.5 per cent to 1.8 per cent.

Last year, Opera began distributing free (but sponsored) versions of its browsers for Mac, Linux and Windows. These carry advertising. Registration, which costs $39, removes the banner ads.

Of the decision to distribute a sponsored form of the browser, Geoff Johnston, vice president of product marketing for StatMarket, said: “This was a smart move, as it seems to have increased its user base. It is proving, slowly but surely, that it can still be a player in the browser war. This should keep Netscape and Microsoft on their toes.”

There's two beta versions of the Opera browser currently available for the Mac: Opera 5.0 for Mac Beta 4 and Beta 2 for Mac OS X. These offer a number of Mac-only functions, including AppleScript support, balloon help and searchable bookmarks. It's a fully-featured browser that supports most major Worldwide Web Consortium standards, and offers 128-bit encryption.