use Module::Require 'require_regex';

    require_regex('Metric::.*');
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From the pod:

This module provides a way to load in a series of modules without having to know all the names, but just the pattern they fit. This can be useful for allowing drop-in modules for application expansion without requiring configuration or prior knowledge.

--
John.

Perhaps autoload can help you avoid having to use them all always?. If not, how about this:

opendir (DIR,"/path/to/dir") or die "Can't readdir: $!";
foreach my $module (grep /\.pm$/, readdir(DIR)) {
  require "/path/to/dir/$module";
  $module =~ s/\.pm$//;
  import $module;
}
closedir DIR;
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I haven't tested this, so you might have to mess with the syntax to require and import.

-- Dan

I'm likely to list all the files explicitly if they are all freestanding packages. I'd probably do this with my editor or code generator if practical.

You also could:

my @reqs = ( "Baz.pm", "Rot.pm" );  
foreach (@reqs) { require; }
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Update: Mispelling, grammar improvement.

BEGIN {foreach (glob "$FindBin::Bin/metrics/*.pm") 
{require;}}
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