I’ve set things so that I have a customized icon if people decide to add this site there favorites list in IE 5+. I don’t think this will work in IE 5 for the Mac but, let me know if it does. What’s a customized favorites icon?
Added (June 12th, 2001): I’ve discovered that this icon idea also works if a visitor bookmarks my site in Konqueror too. So the trick is becoming more cross-platform.
There is also free Java tool that can help you design and build your icons for your sites.