How to -> Add in for IE?

From: harvinder singh (nospam_at_itppppps.com)
Date: 05/19/04 

Date: Wed, 19 May 2004 14:46:09 +0530

Hi,
    I am interested in knowing, how can I write a IE add-in ?. Any source
code links would be valuable.
What I want is, the moment any html page is loaded in IE, It should be able
to iterate the HTML elements and highlight certain words.

Regards
Harvinder Singh