Homepage for the latest version of conserver.
The source tarball for version 8.1.9 of conserver.
Homepage of Stallion Technologies.
Davis Harris' “Minor Scroll of Console Knowledge” contains a heap of useful information on serial consoles and serial communications in general.
The “Greater Scroll of Console Knowledge” contains even more specific information on connecting devices to various other devices. Oh the joy of standards!
Doug Hughes has a similar console server, based on the screen program and an old SunOS™ host.
The Real Weasel company makes a ISA or PCI video card that looks like a PC video card but actually talks to a serial port. This can be used to implement serial consoles on PC hardware for operating systems that can not be forced to use serial console ports early enough.