UPDATE: Merlyn's code above out does what I say here! Listen to merlyn.
I know of no secret pod tags, but you could use a pod hack like the following. I wouldn't recommend it, but it does allow for you to hide at least one line from the pod. The basic premise is -- use a bogus tag and the the perl parser will treat it like but pod parser will ignore it. Anything on the same line as that bogus tag will also get ignored. Not good in wide practice.
#!/usr/bin/perl -w
=head1
Some function or other
=cut
sub foo {
}
=bogustag1
Yet Another function 1
=cut
sub foo2 {
}
=bogustag2 Yet Another function
=cut
sub foo3 {
}
What was wrong with using "#"'s again?
my @a=qw(random brilliant braindead); print $a[rand(@a)];