I'm going to assume this is an "is it possible" rather than an "is it a good idea" question.... You could do something evil with eval, like so:

#!/usr/bin/perl -wT
use strict;

my $x = 1;
my $y = '$x';

eval "$y = 6";

print "X:$x\n";
print "Y:$y\n";
[download]

What do you think the output of the above script is?

Oh, and Sweeper reminded me in another thread of a USENET post by dominus called Why it's stupid to `use a variable as a variable name'

-Blake