Learn how to use procmail, filter or another email filtering
agent. That way, when you see someone post to
news.admin.net-abuse.misc that there is an email spam going around,
you can set up a filter not to see it.
(Mail-Filtering FAQ)
Make sure your system doesn't have any of the well publicized
security holes in it. Look down the list for your type of system, and
make sure that the appropriate patches have been made. (CERT's Advisories List)
If you read Usenet news, here is a system written by the
Cancelmoose to allow you to avoid those annoying massively repeated
articles. (The NoCeM project)
You could learn about these Hate groups on the net. Nothing
negates the effects of their words as well as the truth.
(The Nizkor Project)
Please send me your suggestions for additions to this list!