I suppose someone has probably already done this, but my attempt to find it in SuperSearch failed, so here goes. I have adapted Black Perl so that it compiles in Perl 5. It astonished me how few changes were necessary, and how little they disrupted the mood.

I didn't do this because I like Black Perl (the first time I read it, I thought, "how perverse"), but more because, having read that it would not compile in Perl 5, I felt... challenged. Though in retrospect, it wasn't much of a challenge. Still, here it is...

# Black Perl, adapted for Perl 5 by Jonadab.
# Adapted from Black Perl, as seen in the Camel,
# 2nd ed., p 553

BEFOREHAND: close door, each window & exit;  wait until time;
    open spell book; study; read (spell, $scan, select); tell us;
write it, print the hex while each watches,
    reverse length, write again;
           kill spiders, pop them, chop, split, kill them.
              unlink arms, shift, wait and listen (listening, wait).
sort the flock (then, warn "the goats", kill "the sheep");
    kill them, dump qualms, shift moralities,
           values aside, each one;
               die sheep; die (to, reverse the => system
                      you accept (reject, respect));
next step,
    kill next sacrifice, each sacrifice,
           wait, redo ritual until "all the spirits are pleased";
    do it ("as they say").
do it(*everyone***must***participate***in***forbidden**s*e*x*).
return last victim; package body;
    exit crypt (time, times & "half a time") & close it.
           select (quickly) and warn next victim;
AFTERWARDS: tell nobody.
    wait, wait until time;
           wait until next year, next decade;
               sleep, sleep, die yourself,
                      die @last
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So now it compiles in Perl 5 (tested with 5.6.1), but it still doesn't do anything useful. (I think I'm glad.) I suppose, having taken this step, it is inevitable that someone will also port it to Perl 6, in time. As an interesting side note, if you change $scan back to scan (as in the original) it compiles but dumps core. Maybe I should have left it that way.

sub H{$_=shift;while($_){$c=0;while(s/^2//){$c++;}s/^4//;$
v.=(' ','|','_',"\n",'\\','/')[$c]}$v}sub A{$_=shift;while
($_){$d=hex chop;for(1..4){$pl.=($d%2)?4:2;$d>>=1}}$pl}$H=
"16f6da116f6db14b4b0906c4f324";print H(A($H)) # -- jonadab
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