Running netstat -A inet -lp shows the following...
tcp 0 0 *:798 *:* LISTEN 1043/rpc.ypxfrd
tcp 0 0 *:1003 *:* LISTEN 822/ypserv
Then a little googling and I find that these daemons are part of NIS (Network Information Service). Formerly known as the Sun Yellow Pages (explains the ypserv & ypxfrd).
Turns out these littl' buggers distribute information across a network, like login names/passwords/home directories/group information/host names/ip numbers. The purpose of all this is that if you have a group of machines all running NIS and your password is stored in the NIS database then you can login into any machine of the network that is running the NIS client program. Needless to say....I turned this service OFF. Thanks for you reply, markus1982.