A look at social sharing on the new RockMelt browser.

Little has been known about stealth start-up RockMelt except that it's a browser, specifically (and yet ambiguously) a "Facebook browser," and it's backed by browser godfather Marc Andreessen. Well, now RockMelt has crept out of the woodwork into a limited beta for Mac and Windows, and the world can get a peek at it.

RockMelt is indeed a "Facebook browser," if only because Facebook is the social-media service that's best integrated into it at launch. It's clear that ultimately the browser's team plans to make it more customizable with other services. The ultimate goal, you could say, is revamping the traditional browser many of the Web-browsing behaviors that have popped up in the past few years--social-media sharing, Twitter clients, RSS alerts, and speedier search--and works them into an interface that aims for convenience rather than confusion. While it may still have too many bells and whistles for the average Web user, it's likely to attract some curiosity from hardcore social-media users, obsessive multitaskers, and efficiency geeks who see an opportunity to cut down on the number of browser tabs and desktop applications that they may have open.

"We're reinventing the browser for how people user the Web today, which is dramatically different from how people were using the Web only a few short years ago," RockMelt co-founder Tim Howes told CNET.

First of all, you log in with Facebook Connect upon launching RockMelt. There's a left sidebar of easy Facebook access, including a row of "top friends" that you can select, and you can drag or drop content from the main browser (like links or videos) to immediately share it with one of them in Facebook Chat. (Unfortunately, there is not yet support for other instant-messaging clients.)

Then, on the right side bar, is a customizable list of favorite sites and services, with yellow indicators to tell you when there's new content from a blog you read or the people you follow on Twitter. There's a browser button to share content on Facebook or Twitter (and more services to come)' the company even has its own URL shortener, http://me.lt.

The search box at the top is also different than your average browser's. It loads up a list of results in a drop-down menu, and begins "preloading" all of them so that you can flip back and forth between individual results at maximum speed.

"It changes the way you search because it makes it so much faster and so much lighter-weight," co-founder Eric Vishria explained.

The term "social browser" has been thrown about before, namely three years ago with the launch of Flock, a Firefox-based browser loaded with a dizzying number of social features. RockMelt certainly looks a lot cleaner. Built on Chromium, the foundation of Google Chrome, it aims to be fast, too.

Will people actually switch over to it Vishria raised a statistic that in the past three years, 500 million people have switched browsers, so that getting them to switch again may be less difficult than it sounds.

RockMelt employs about 30 people, has been in the works for two years, and has raised about $10 million in funding from the Andreessen Horowitz venture firm as well as other investors like Josh Kopelman of First Round Capital and ubiquitous angel investor Ron Conway.

And its odd, vaguely geology-evoking name It "came out of a three-week brainstorming sesion where we had a million different names," Howes said. Added Vishria: "Easy to spell, easy to remember, and the domain was available."