I have HP's all in one device which is ethernet enabled. So all computers on the LAN can print to it/scan from it etc. The printer seems to use DHCP server to acquire the IP address and did not provide any name to the DHCP server. The windows version of software managed to detect the printer correctly and also everytime the address is changed. Then after the obligatory nmap port scan I discovered that it runs something called rendezvous protocol for autodiscovery. This is now standardized by IETF Zeroconf working group and is promoted by apple for seamless network configuration, autodiscovery etc. for SoHo users (and used by iPod, is built into MacOSX etc.) This also seems to be supported by HP, IBM.

There is ofcourse a competitive proposal called uPnP
(universal plug and pray play) which is endorsed by Microsoft.

Anyway, found some interesting links on zeroconf:
A very good article on O'Reilly network about zeroconf.

An interview with Stuart Cheshire (now with Apple) who authored zeroconf IETF RFC's.

An interesting thread on linux mailing list about adding this stuff to linux and politics behind such a thing!

Python and its implementation of zeroconf.