Cameo appearances include: Adam Levine, Jesse Carmichael of Maroon 5, Josh Groban, Pharell Williams of N.E.R.D., Jennifer Nettles of Sugarland, Ben Folds, Ryan Tedder, Laura Jansen, Ingrid Michaelson, Vanessa Carlton, Tegan and Sara, Cary Brothers, Greg Laswell, Adam Gardner and Ryan Miller from Guster, and Keenan Cahill