Continuing the erosion of Web page identity, by which Web pages become iGoogle-style generic frameworks for plug-in application modules, Google on Thursday added a Web search box to Gmail, as a Google Labs experiment.

This might seem redundant: In addition to this new search box in the left-hand navigation bar of the Gmail in-box, users also have the option of using two other search boxes, one at the top of the Gmail page and one within the browser chrome -- the Web browser window frame -- typically positioned to the right of the address bar.

Just as razor makers pushed double-, triple-, quadruple-, and quintuple-bladed razors as improvements on the single-bladed variety, Google appears to be convinced that one can never have too many search boxes.

At the same time, the new left-hand column search box offers a different user experience than the top-of-page search box, which opens a new Web page/tab following a query, or the in-chrome search box, which overwrites the active Web page by loading the search results page (at least in Firefox).

The Google Labs search box lists search results in the lower right-hand corner of the Gmail page in a floating window pane, where they can be accessed along with the rest of the Gmail links and options. Its use thus does not require any potentially disruptive tabbing or application switching.

Using the Google Labs search box also doesn't return any ads, unlike the typical Google search results page. Perhaps this oversight will be remedied if this new search experiment graduates to official release status.

What makes the Google Labs search in Gmail particularly useful is the arrow icon to the left of the search results, just right of the search results window scroll bar. When clicked, the arrow opens a drop-down menu that lets you send selected search results via chat or e-mail to whoever you're corresponding with. This is significantly more convenient than application switching, copying, and pasting, particularly when used in conjunction with keyboard shortcuts.

As to whether Web pages will truly become generic placeholders for plug-in services, there's reason to believe there are limits to the amount of functionality that can be crammed onto a single page.

It's a problem that Google engineer Adam de Boor acknowledges in his blog post about the new Google Labs search feature. "[W]ith all the stuff we've been adding to Gmail Labs lately, the left side of your account might be getting crowded," he observes.

Though he points to a Google Labs feature called "Navbar drag and drop" that can mitigate the crowding problem, such workarounds can only do so much.

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