"Proud to Be Loud" Performed by The Dead Green Mummies -- this song is actually performed by the band Pantera. (The Dead Green Mummies do not exist.) Pantera has all but disowned their first four albums, this song is track 5 on the fourth of those albums, "Power Metal." The band presumably did not want to be credited with the song (as they don't consider any of their pre-1990 material part of their discography) and made up the name The Dead Green Mummies.
After the closing credits, on the director's cut, there is the title of the movie followed by a drawing of Frank.