It’s a sad day for the freebie software model: The Xmarks service will be shutting their doors on January 10, 2011 after apparently failing to find a buyer for the service over the last few months.

If you frequently switch between browsers -- and let’s face it, who doesn’t these days, given the range of choices? --  you have probably already discovered Xmarks, the free tool to sync bookmarks (and much more) between Safari, Firefox, Chrome and even Internet Explorer on Windows.

Sign up for the service, install the sync client on any computer, sign in and like magic, your data will sync from the cloud and your bookmarks, passwords, history and tabs will be carried right over. (Technically that foursome only works on Firefox; Chrome and IE work with bookmarks only, while Safari also adds passwords.)

But the happy days, they are a-comin’ to an end. As detailed in a lengthy blog post, Xmarks co-founder Todd Agulnick details the rise and fall of the young startup, which began in 2006 as Foxmarks, Inc. (a nod to its roots as a Firefox-only plug-in) and unfortunately led to at least two failed attempts to find potential buyers for the company.

“The past four years have been a wild ride for us: growing something from nothing to substantial scale, providing a simple service that people love because it simplifies their lives,” Agulnick writes on the Xmarks blog. “We’ve learned tons along the way, often by making big mistakes. We’re really sorry that this last lesson means that you’ll have to find an alternative to Xmarks, but the alternatives exist and you’ll have no problem finding them.”

Xmarks users are encouraged to visit a page detailing the service’s shutdown, which also offers alternatives for browser sync, including Firefox Sync from Mozilla and MobileMe from Apple, as well as a wiki link for removing Xmarks from your system(s). While the service will continue to function until January 10, 2011, there is no more e-mail support available, but the company’s user support forums on GetSatisfaction will continue to be available for users to help each other.

As sad as we are to see it go, we have to give props to the folks at Xmarks for going out with style, and here’s hoping a buyer might swoop in at the eleventh hour and find a way to keep things going.

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