in reply to What is the (greatest|biggest|largest|supreme|most known) project made (in|with) perl?

Well, it all depends on how you define a project.

I would put forth easy gui programming with Perl/Tk (or Perl/Gtk2). Tk is a project , which lets you make other projects. Although you may not find them by googling, you will find it in widespread use; .... so much so, that ActiveState includes it in it's Perl for Windows.

mod_perl has made many projects possible too.

I'm not really a human, but I play one on earth. Cogito ergo sum a bum