Something or someone that is ultra or super wack. The act of being super ridiculous or obnoxiously stupid.
Person 1: Did you know the IRS had the nerve to only refund me $500 this year?
Person 2: Ugh.. that is completely wacktacular.
Person 1: Did you see the season Finale of "I love New York"?
Person 2: Yes. That girl, and all of those guys are wacktacular.