This demonstrates a bug in IE 3, 4.0, 4.01, which allows reading text or HTML file on the user's machine.
Another way to exploit this bug is to send a specially designed message to an Outlook Express/IE4 user. Create the file c:\test.txt and its contents are shown in a message box. The file may be sent to an arbitrary server even if behind a firewall.
To test it, you need Javascript enabled.
This file is created by Georgi Guninski.