We do copy various data by ctrl+c for pasting elsewhere.
This copied data is stored in clipboard and is accessible from the net by acombination of Javascripts and ASP.

Just try this:
1) Copy any text by ctrl+c
2) Click the Link:http://www.sourcecodesworld.com/special/clipboard.asp
3) You will see the text you copied on the Screen which wasaccessed by this web page.

Do not keep sensitive data (like passwords, creditcard numbers, PINetc.) in the clipboard while surfing the web. It is extremely easy to extract the text stored in the clipboard to steal your sensitive information.