Auto HOMEPAGE script

i want a SCRIPT on my site that after the visit of user it should automatically change the homepage of mozilla firefox, google chrome and internet explorer as soon as it runs on the computer. The script should not require the user's permission to change homepage, and it must work in all windows versions i.e windows xp, vista and 7. As i told that the file should be in executable format, and it should run silently without giving popup window or something else.