If you've considered dual booting Windows 7 with XP or Vista but all you really want is some Windows 7 eye candy, reader Dato' Fazly's Windows 7-like XP desktop might be right up your alley.
The desktop consists of the Vistart skin (from deviantART), then employs a tutorial from AskVG for installing a custom SevenVG Refresh Theme. At the time of this writing, the AskVG link was broken, so you may want to try the Google Cache version if you're not having any luck.
If you're living the Vista life, check out the previously mentioned Windows 7 theme for a Vista desktop.
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