Re: @boxplayer - "Nobody uses it..."
"How did we ever manage to migrate from IPX to TCP?"
TCP/IP IPv4 was the hacky kludge we implemented whilst the Internet protocols were being developed. That turned out to be IPX and was unroutable. (IPX = "Internet Protocol Exchange" aka IPv5)
Anyone using IPX was in an island of their own or a couple of isolated offices until they accepted the inevitable and switched to TCP/IP.