Pulled straight from the Internet Explorer 4 resources. Don't know how many people ever found this easter egg but it's there in Internet Explorer 4.
There's a TON of funny stuff in these credits. Scratch-'n-sniff toolbars, The Grim Reaper, caffeine, caffeine, more caffeine, the French Espresso cart and more. There's even a reference to the Microsoft Bear and Microsoft Bunny.

Now since none of us use Windows 98 anymore, here's the link to the credits: http://www.beige-box.com/ie4
It only seems to work in Internet Explorer. Suprising? Well, this was 1998 and I guess that the entirety of this easter egg was written using stuff only Internet Explorer would understand. Not tested in IE 9 or IE 10 PP.
If you get warned about potentially unsafe ActiveX controls, just say Yes. Again, these were pulled straight from the IE4 resources and I've done nothing to them except for modifying the script some to allow it to run on any version of Internet Explorer.

It half-works in IE9. Incredibly fast scrolling so it's near-impossible to read.

This problem seems to be related to this bit of JavaScript:

Setting to anything higher than 11 causes the scrolling text to quit working.

I'll look at this stuff tomorrow in my Windows 98 VM (or should I use 98SE? Will either work?). What file did you find this in?

You need Internet Explorer 4 so either Windows 95 with IE 4 installed or Windows 98 First Edition.
Here's how you can activate this egg: http://eeggs.com/items/729.html

Oh my god. That thing gave me a near-seizure in IE9! Blargh!@