MIT may have had its own server, not conected to any other network
they could have had their server linked to any number of networks, notably EFnet undernet DALnet and my brain fails me, but there was another major net before the explosion of networks we have now, and depending on how long ago you are talking about it could have been any that have come and gone. however you can try the different nets and wander about looking in channels, you will eventually stumble over someone "from back then"
look for blogs by people you knew then
I'm sure MIT.edu still has a server, you just can't get there from here
