Best known as the lead vocalist and primary songwriter for the rock band Relient K, Thiessen has also co-written numerous songs for other artists, most notably Owl City and Katy Perry.
VeggieTales: Merry Larry and the True Light of Christmas 2013
Songs
Wreck-It Ralph 2012
Relient K: Live at Capitol Studios 2007
as Himself
Credits from TMDB.