When a project calls for self-modifying or self-reading code {g}, I like to stick my code in $_ and eval it like so:

$_='
#obfuscated
#self-modifying code
#here
#and then
eval
#again if you want to get really messy
',eval;
[download]

Of course, there are other, more obfuscated ways to go about doing this too :-)

   MeowChow                                               
                print $/='"',(`$^X\144oc $^X\146aq1`)[-2]