How to show live preview in a small popup of linked page on mouse over on link?

Question

How to show live preview in a small popup of linked page on mouse over on link ?

like this

http://cssglobe.com/lab/tooltip/03/

but live preview

Answer 1

Another way is to use a website thumbnail/link preview service LinkPeek (even happens to show a screenshot of StackOverflow as a demo right now), URL2PNG, Browshot, Websnapr, or an alternative.