If ikegami's excellent suggestions aren't enough, there's also a Bit::Vector module on CPAN.

One nice thing about the bitwise operators in Perl is that you can use them on whole strings, not just on integers. For example,

use strict;
my $x = "abcdefghijklmnopqrstuvwxyz";
my $y = ("A" ^ "a") x length($x);
my $z = $x & ~$y;
print "\$z = $z\n";
[download]

This outputs $z = ABCDEFGHIJKLMNOPQRSTUVWXYZ. (This is just an example, not recommended for case conversion because it screws up non-alphabetic characters.)

You should also be aware of pack/unpack "H*", pack/unpack "B*", or "b*, to print bit strings for debugging, to input long constants, etc.