Alternate working title: How to lose friends and alienate people.
(^^^) and <(") which render a little shark and penguin, respectively. I know, right!?
Now that your mind is well blown, for my grand finale I will demonstrate how to put smiley faces in the background of your facebook page. I know, just what your life was missing. When you're on facebook, copy and paste this entire line into your address bar and hit enter:
Pretty harmless stuff. It's visible only to you and will disappear when you refresh the page or anything like that. Tested in firefox, ie8 & ie7.