http://jsfiddle.net/ http://jsfiddle.net/ Or If you just want to manipulate others web pages it can be done by pasting into your browser's address bar. javas

http://jsfiddle.net/ http://jsfiddle.net/ Or If you just want to manipulate others web pages it can be done by pasting into your browser's address bar. javascript: code here To make a bookmarklet paste into any bookmark address.