WP Admin Toolbar Gone On Front End

For some reason, the wordpress admin toolbar (top) is just gone on the front end. It’s fine in the back end. The only thing I’ve really been doing lately is adding things to my theme’s functions.php file, but it’s not my theme because I tried switching to the twenty-ten theme (and twenty-eleven) and it still doesn’t show up on the front end. I even disabled all plugins and still not there. I didn’t even know you could turn it off, can you?

What did I do by mistake here?

There seems to be a space for it above the body element (at least the body element in firebug shows as beginning below where the bar would normally be) but I have no way of knowing if this means that it’s still creating a space for it or not as I don’t remember where it used to sit in the html markup.