Perl's laissez faire approach to OO. Most people bitch and moan about it for one reason or another, but I like being able to be as OO as I want to be... or not. It's just so damned easy to do exactly what I want, I figure those that complain are either grinding axes or bondage freaks.
Punctuation. I love punctuation. It doesn't look like programming without the line noise. Do this, don't do that, can't you read the signs?
Built-in networking and IPC functions. This is what turned me on to Perl in the first place (and scarred me for life from TCL). We don' need no steeeenkin modules.
Globs. They're fun to say. GLOB GLOB GLOB GLOB GLOB. And they're fun to use.
package variables. It seems everyone's got a hard on for lexicals. my() this, my() that. Sounds like a bunch of three year olds. Gimme a namespace and chuck use strict and I'm happy. /me hugs local() too
Punctuation variable names. Wait. That goes with my punct fetish.