This is an extension for Firefox that supposedly also works in IE 6. I have this installed and would like to try it out - anybody care to be a guinea pig with me? Tried to connect to a colleague upstairs, but he couldn't connect for some reason (obviously this isn't ready for prime time yet). I'm out of the office this afternoon, but drop me an email if you want to try this out and we'll set up a time...
" Jybe is an extension for Firefox that allows you to link your browser together to one or more friends' browsers and allows you to chat and browse the web together. Initial features included full frames support, chat, and a powerpoint presentation system, with more to come. Additionally, our plugin for Firefox is cross compatible with our identical plugin for Internet Explorer. Users of Firefox in Windows, Mac, Linux etc. can collaborate with users on any OS, and even users of Internet Explorer."
Link: Jybe Beta Released