At a Glance
If you appreciate beautiful photography, then download Midtown Remake. This free Windows 7 theme features a moody black-and-white interpretation of midtown Manhattan by Nero99, a talented photographer and digital artist. Although there's only one wallpaper in this theme, it's well worth the download.
The folks at Free Windows 7 Themes who put together this theme included the high-def wallpaper image, set the window color to a complementary taupe, and selected Microsoft's Landscape for sounds. All in all, it's a nice package.
Note: To install this theme, just uncompress the zip archive and double-click the themepack file within. Windows does the rest.