I'd say a slight majority of the non-pragma modules I use are OO so it seems odd that you've managed to escape it. Here are some examples, though a few sport non-OO interfaces too-

• URI
• Path::Class
• DBI
• XML::LibXML
• WWW::Mechanize
• CGI
• IO::Handle
• JSON

In their own realms, they offer great examples of when one might use OO. And when you are using 60 modules in a script, OO is nice for the simple fact that you have inlined, by the object's name, a good map to the functionality's origin. $mech->get(...) is easier to grok and backtrack to perldoc WWW::Mechanize than get(...) would be in a couple thousand lines of code.

Perl's OO ecosystem is excellent. If you're just starting out with it and want a leg up, I'd point you at Moo before Moose.