Although it seems obvious to most perlmonks,
in reply to Things every perl programmer should know?
are often missing from programs that I see. Perl newbies need to know that using this modules will help create clean portable code faster than without them.
In the bigger picture I think perl users (indeed all programmers) need to better educate themselves on network and system security. Learn how the code you write can affect others. The server is not a island. What you do cause others to have a very bad day.