http://m.lifehacker.com/5619064/w7-theme-for-ubuntu-brings-windows-7s-familiar-gui-to-linux
W7 Theme is a free script that skins your Linux desktop with a familiar Windows 7 look and feel.
Click on the image for a closer look.
We recently shared a program that makes your Windows machine look like OS X; W7 is a similar tool that changes your Linux GUI to a more familiar Windows interface. Linux has a highly configurable GUI, but if you long for the more well-known Windows interface, this script will do a remarkably good job of making Ubuntu look like Windows 7. You can download either a GNOME and KDE version, as well as one of a few Firefox themes to make your browser look more Windows-y too.
You'll need to do a bit of Terminal work to install the theme, though if your copy and paste skills are up to snuff, you should be fine. It's pretty handy if, say, you have a relative who needs to use Linux but is confused by the interface (or you just really, really like Aero Glass). The only downside is that there's no easy uninstall procedure at the moment—so make a backup before you install it in case you decide you want to switch back. W7 Theme [Maties Ubuntu via #tips]
