Les Luthiers' Teresa y el Oso, which directly parodies Peter and the Wolf, does this to the extreme. The characters also have silly rhyming names in Spanish: "El Pajarillo Amarillo" (The Yellow Birdie), "La Mariposa Golosa" (The Sweet-toothed Butterfly), "El Molusco Pardusco" (The Brownish Molusk) and, most notably, "El Oso Libidinoso" (The Libidinous Bear).
"Weird Al" Yankovic: "And of course, as always, the part of Bob the Janitor is played by the accordion." (He also tried to get Don Ameche to play the grandfather, but was stuck with a bassoon instead.)
Richard Wagner may be considered the KING of the Leitmotif; though he was not its inventor, he certainly made the most extensive, elaborate, and probably the most intelligent use of it throughout the canon of his works. His great Ring Cycle, for instance, consists almost entirely of a symphonic/dramatic development and interweaving of motives and themes and had a good 30 or 40 different ones in it!
Jim Steinman, best known as the songwriter for Meat Loaf's "Bat Out Of Hell" albums, interconnected many of his songs with stock phrases, imagery, and leitmotifs. Not surprisingly, he coined the term "Wagnerian rock" to describe his style.
Death metal band Bolt Thrower have the centrepiece song on most of their albums begin with a fade into the same riff, developing over the years. In its first iteration, World Eater, and in most since, it is also the outro to the song.
Richard Strauss's "An Alpine Symphony" has several leitmotifs of descriptive significance. One of the main themes is the "Ascent" motif, an inversion of which is used for the descent.
The Beach Boys/ Brian Wilson's S Mi LE features multiple, distinct variations of the Bycicle Rider theme and of the centerpiece Heroes and Villains; so many ,in fact, that most of the songs of the album could be thought as subsections of it. Its actual symbolism is up to discussion, due to the fragmented and unfinished character of the work, but it seems to represent the theme of travel throughout history and America from Plymouth to Hawaii.