Today is the day! You, your dumb little buddies, and anyone else can now buy the all-new unrated cut of Jackass Presents: Bad Grandpa as a Digital HD download on iTunes. Why is it important that you do this as soon as humanly possible? Because later today—at 5:00pm PST to be precise—you can participate in a LIVE Twitter Viewing Party with Johnny Knoxville himself. That's right, the official @realjknoxville you've come to know, love, and wahoo along with since jackass broke its first windy on MTV in October 2000. In addition to the watch along though, you can play along as well if you register for "Grandpa's Bad Board" game over at the http://j.mp/GrandpasBadBoard home page. Look for further news, updates, and associated whatnot to appear later today on the official jackass Facebook page and @jackassworld Twitter feed.