TCPSER is a Windows program that allows a serial port to function as an emulated Hayes-compatible modem, with the phone connection replaced
by TCP/IP. The author reports that it is being used by a number of folks to bring up vintage “telnet” BBS systems on older 8-bit computing platforms. Others are using it as a low-cost way to put older computing systems on the Internet. TelBBS offers lots of resources for how to take advantage of this cool idea.