In this episode of College GameDay Flashback, Christine Williamson and the GameDay crew recollect the most memorable celebrity guest pickers in the show's history. 0:00 It begins with Charles Barkley 1:55 Great guest pickers of history 4:25 The Katy Perry takeover 7:27 What makes a good guest picker? ✔️Subscribe to ESPN+ http://espnplus.com/youtube ✔️ Get the ESPN App: http://www.espn.com/espn/apps/espn ✔️Subscribe to ESPN on YouTube: http://es.pn/SUBSCRIBEtoYOUTUBE ✔️ Subscribe to NBA on ESPN on YouTube: http://bit.ly/SUBSCRIBEtoNBAonESPN ✔️ Watch ESPN on YouTube TV: http://es.pn/YouTubeTV