This is the new feature (one of them) in IE9 I was telling you about.

Pinned shortcuts are the killer feature of Internet Explorer 9, as I noted in my review of the IE9 beta yesterday. (For a quick refresher on how pinned sites work and why they’re so useful, see “Treating websites as apps.”)
The most common scenario for using pinned apps is to put them on the Taskbar, as I illustrated in my report (and as Microsoft has showed off in their demos). Indeed, that is the right choice for your absolute favorite sites, the ones you use all the time, like a web-based mail client or your Facebook or Twitter page. That lets you treat the site as if it were an app. And as I pointed out earlier, you can also open additional tabs alongside your pinned site to keep groups of related tabs in the same window, identified on the taskbar by the icon of the pinned site.
A closer look at the Internet Explorer 9 beta (screenshots)
But if you just look at the official demos, you might not be aware of a few cool tricks you can try with pinned shortcuts.
(A note right up front: IE9 doesn’t run on Windows XP, so everything in this post is intended for users of Windows 7 or Windows Vista with SP2.)
To master pinned site shortcuts, you first have to understand what they are.
Under the covers, IE9 saves pinned shortcuts using a new registered file type for Windows, officially known as a Pinned Site Shortcut. It is almost exactly like a regular Internet Shortcut except that it has a .website file-name extension instead of a .url extension. In fact, you can turn a regular web shortcut into a pinned site shortcut, or vice versa, by changing the extension.

Although Microsoft’s demos make a big deal out of the Windows 7 Taskbar, you can actually create pinned shortcuts anywhere in the file system. So, you can drag the icon from the address bar onto the Start menu to pin a shortcut for the current page to the top of the Start menu. If you want a pinned site shortcut on the All Programs menu and not at the top of the Start menu, tap the Alt key to make the classic menus visible, then click Tools, Add Site To Start Menu. (The keyboard shortcut is Alt, T, M.) You can also drag that icon onto the desktop, or into any Windows Explorer folder to create a perfectly good pinned site shortcut there.
And although you can’t pin a shortcut to the Taskbar in Windows Vista (that feature is new in Windows 7) you can create and use pinned sites on the Start menu and the desktop.
There is nothing magical about a pinned site shortcut. The .website extension tells Windows to call Internet Explorer with a set of special startup switches:
“C:\Program Files (x86)\Internet Explorer\iexplore.exe” -w “%l” %*
The –w switch is what causes Internet Explorer 9 to treat this process as a pinned website rather than a standard web page. The remaining parameters tell IE9 to use the saved location and any other switches from the saved shortcut.
For your most favorite favorites, the websites you visit every day and leave open all day, it makes sense to pin them to the Taskbar in Windows 7. But for other sites, you might want to preserve this option without cluttering up your Taskbar. For those sites, use the option to save them to the Start menu. The advantage is that Windows categorizes pinned site shortcuts (the ones with the .website extension) as programs for search purposes, and it returns results from the Start menu instantly, before it even begins to search the rest of the index. Thus, when you start typing a search term, you see a listing at the top of the Start menu that includes both installed programs and websites you’ve saved as pinned shortcuts. When I type the letter Z in the Start menu search box, here’s what I see:

To  take maximum advantage of this feature, use the Alt, T, M shortcut and then edit the properties of the saved shortcut so that it has the name you want, not the one the site designer assigned. Click Start, click All Programs, and then right-click the shortcut and click Properties. That opens the Properties dialog for your saved website shortcut. In the box at the top of the General tab, give it the name you want to see (and search for) in the Start menu. On the Website tab, you can edit the Start URL if it includes details you don’t need, and you can also customize the Tooltip Name so that it accurately describes the site itself.
If you want to customize pinned shortcuts on the Taskbar, you’ll find them all in this folder:
C:\Users\<Username>\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar
Pinned shortcuts on the All Programs menu are here:
C:\Users\<Username>\AppData\Roaming\Microsoft\Windows\Start Menu\Programs
I’ve found a few more neat tricks that IE9 is capable of, and I’ll share them in a follow-up post.
Update: In the Talkback section, Speednet provides a nifty list of some of the other advantages of pinned shortcuts:

The big features (only available for Windows 7 users) is the ability for Web sites to directly interact with the pinned shortcut. Those interactions are directly controlled through META tags
and JavaScript.

If you’re a web developer or even remotely interested in the topic, the full comment is well worth reading.

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