LOL, right you are about netbeui and netbios. Too bad it wasn't routeable because it is fast and easy.
But you can run netbeui on XP:
http://support.microsoft.com/default.aspx?scid=kb;en-us;301041&sd=tech
Pretty sure you have to add TCP to '98 and that is clearly the easier way unless Curlesw doesn't understand segment and subnets. Then Netbeui is just plug and play between 2 PC's.