Do you wish to customize your computer? Do you want to have a perfect customization for you? If so, you should try Rainmeter.
Rainmeter is a program that let you customize your desktop by adding customizable skins. For example: a clock, bars that show the mermory used, the CPU usage, etc. If you want to create your own skins, you need to have knowledges about computer language.
If you just want to download your skins on internet without creating yours, just go to some links that present rainmeter skins. The one I always use is Devianart. There are also others like customize.org, skinbase.org...
Link to download Rainmeter: Rainmeter.net
Here is an example of skins I used to customize my desktop. If you like it, you can find it on devianart.