I came up with the worst idea this morning, around 8:54 AM EDT. 
(from #irc.linux.com::perl)

<japhy> wow.
<japhy> no, I just gave myself a difficult challenge.
<evilgwynie> what is that?
<japhy>   $regex =~ $regex;
<japhy> create a pattern that matches itself, and NOTHING ELSE
<evilgwynie> hmm

[download]
Ugh. What did I get myself into?! I labored for an hour or so, and I've not been able to get anything concrete.

One large problem is the exponential increase of backslashes: 

to match     you need          backslashes
--------     --------          -----------
^            \^                1
\^           \\\^              3
\\\^         \\\\\\\^          7
\\\\\\\^     \\\\\\\\\\\\\\\^  15

[download]
That pattern is, of course, 2**n - 1. It is super icky.

japhy -- Perl and Regex Hacker

In reply to japhy has met his match by japhy

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