It might be possible... if you have some sort of PBX software and can push out a dialtone to the other. Assuming you really do mean connecting two machines via the modem jacks, not the serial ports. I can't imagine it would be easy nor terribly fast. If they have serial ports, use them. It should have a parallel port, so you could use laplink cables to connect the two. But what are you trying to do? Are you trying to get data from an old laptop to a newer one? If the newer one does have USB, then you can get a 2.5" IDE external enclosure for $10 or so. Pop the drive out of the old machine, put it in the enclosure, hook it up to the new machine and transfer your files. Much easier and faster than any serial/parallel transfer. If you're trying to network the two for live file sharing and such, it's probably worth investing in a PCMCIA network card.