wconsd is a serial console server for Windows NT/2k/XP. It maps local com ports to an IP socket and makes it accessible with any TCP/IP terminal. I use it with PuTTY to set up routers when no IP address is assigned… PuTTY just feels better than Hyperterminal or TeraTerm;)
→ downlad source code
→ downlad binaries
update: PuTTY 0.59 (Jan 24, 2007) includes native support for serial consoles.