Experimental builds of Firefox Web browser are trying out a new keystroke navigation system for skipping through links on a page, the Mozilla Foundation said Tuesday.

The two special builds-- one for Windows, the other for Linux-- include a feature dubbed "spatial navigation" originally designed for browsing on a TV using a television remote controller.

Rather than point and click with the mouse, these Firefox builds let users apply the Shift and Alt keys, then one of the four cursor keys, to move to a nearby link on a Web page.

Although that idea is far from new, the spin here is that the keystroke combinations take users to the next link by visual position, not its place in the HTML source code. To move to a link immediately to the right of the current link, users would press Shift-Alt-right arrow.

Opera, which just revved to version 8, has a similar feature.

According to Asa Dotzler, an engineer with the Mozilla Foundation, "the feature will be evaluated for possible inclusion in later Firefox releases."

The Firefox builds can be downloaded from the Web site of their creator, Doug Turner. He is the lead developer of Mozilla's attempt to create a miniature version of the open-source browser for small-screen devices, such as cell phones and PDAs.