I agree with John in general terms. NIS has come a long way since the early days though. For "simple home networking" I wouldn't bother with it. Just scp any files you need (hosts, passwd ...) under cron control. The issue that any host who can guess your NIS domainname can access your password file is valid, but NIS servers can be configured to only answer requests from particular IP ranges, so setting this to your local LAN should do the trick. Also if someone can connect to your internal port 111 from outside your firewall then you've got bigger problems. I don't run NIS at home (5 machines) but have set it up and used it under SuSE, HP-UX and Solaris on Corporate networks with over 400 NIS clients and there, without doubt, there is no viable alternative :o)
Don't get me wrong, NIS is not "undoable". It just requires vigilance. Some of the earliest and most famous exploits involve NIS. It does have it's uses, but it's not needed for simple networking (taking from the name of the thread).
Damian