A phrase to imply that someone is a SERIOUS tool (insult), or that done something really toolish.
Rosie: Wtf? Why the hell did you feel the need to buy the Avenged Sevenfold t-shirt that I was saving up for!? There were loads of different types that you could have gotten!
Emily: To piss you off.
Rosie: Well I guess that makes you a TOOLY MCTOOLIGAN...