One liners are bad enough; but I swear, "shelling-out" to actual Perl scripts from a Perl script is one of the most offensive things I can see in Perl code.

My opinion is actually the other way around: system, when used properly, is less bad than using qx//, because the latter almost always involves the shell and introduces quoting problems - though what I said above still stands, calling another perl is almost never necessary (the most common exception I make is during testing). See Calling External Commands More Safely and The problem of "the" default shell.