package Utility;
...
my ($cgi, $session, $dbh, $config, ...); # create (but don't set)
                                         # important variables
# do miscellaneous stuff
...
init();
...
sub init {
   $cgi = CGI->new();
   $session = CGI::Session->new( $params );
   ...
}

# later on
sub get_session_param {
   my $p = shift;
   return $session->param( $p );
}

sub set_session_param {
	my ($p, $val) = @_;
	$session->param( $p, $val );
}
# plus other stuff for interacting with $session

sub param {
    my $p = shift;
    return $cgi->param( $p );
}
# plus other cgi interactions

# 9950 lines of other code
# (including similar code for setting up database handles, http clients, and
# other functionality that I have roles for)