This is my first attempt at obfuscated Perl. It really rubbed me the wrong way to write it, since I'm such a stickler for maintaintable, readable code. I currently use this as my .signature.
perl -le '$"=$,,@_=(1)x4,@a=(0,4,5,4),map{$_<<=6,$_+=13}@_;for(0..
3){$_[$_]+=1<<$a[$_]if$_;$_[$_]+=$a[$_]}$_[3]+=10,print map chr,@_'
I worked pretty hard on getting it as short and obfuscated as possible. There's a neat trick I used in there with the @a array. It happened to work out mathematically in my favor.
I welcome feedback and/or improvements. :)
