Do you love the Mac's desktop, but can't stomach the Apple tax? Forget those lame themes and install the Snow Transformation Pack, a free Windows software that makes your entire system look like OS X.
Created by WinXSoft, the freeware does more than change a background, use different fonts and add new icons like typical themes. Instead, it recreates the entire Snow Leopard UI, making your Windows 7 or Vista desktop feel legitimately like a Mac computer. Plus, you can still play games and not rave like a fanboy, which are always awesome qualities to have.
The Snow Transformation Pack replaces a whole host of components, such as system icons, system sounds, graphics, wallpapers, login screen, shutdown dialog box and system branding logo. It also throws in additional applications to emulate Snow Leopard features, such as the Dock, Spaces, Shadow and more. Simply put, it goes above and beyond what OS X themes for Windows usually do - potentially changing your entire user experience.
You get three options for the installation: Complete (which installs everything), Performance (which changes the UI, but doesn't add new applications such as the OS X Dock) and Custom (which allows you to pick and choose individual tweaks you want implemented). User Account Control will need to be disabled to install it. Also, make sure to run a backup beforehand, just to be safe.
If you're sick of the usual Windows UI, the Snow Transformation Pack looks like it offers a seriously extensive replacement that brings the Mac experience to your non-overpriced machine. You can download it for free from the link below.