This definition of "quodlibet" is for singers who like to show off their vast knowledge of songs..
I like the idea of putting several well-known melodies together "sequentially for humorous effect." My family used to play The Quodlibet Game as we would take long car rides together. One person would start singing a song. Then another person would change the song by cuing off one of the words in the previous song. Then another person would start a new thread with another song cuing off a word, and then another, and another. (You had to be thinking ahead so that you could seamlessly cut in and start a new song tangent.) However, you were allowed to begin the new thread with a second or third verse or chorus or even a random word in a phrase. The first person has to keep singing until someone else comes in, and no one can repeat a song during a single round. It is not an easy game.
For example, we might play The Quodlibet Game using just Broadway show tunes, Christmas Carols, Disney songs, Folk songs or Pop songs. etc. The hardest part is staying in the theme category. If you use a song that is not in the approved category or you just blow the words, you stop the round and get a negative point. If everybody else is stumped, the ending singer gets a positive point. (Of course you could always play it without a specific category where any song is fair game. That's for amateurs, though.)
Category: Christmas Songs
1. "While by my sheep I watched at night, Glad tidings brought an angel bright, How great my joy___"
2. "Joy to the world the Lord is come Let earth receive her king___"
3. "King of Kings __(Hallelujah, Hallelujah) and Lord of Lords __(Hallelujah, Hallelujah) And He shall___"
4. "He shall feed his flock like a shepherd___"
5. "Shepherds shake off your drowsy sleep, Come___"
6. "Come all ye children good tidings for us___"
7. "For unto us a child is born, unto us a child is given,___"
Category: Folk Songs
1. "Oh Shenandoah, I long to see you, away you rolling river, Oh Shenandoah, I long to see you away___"
2. "Away down south in the land of cotton, old times there are not forgotten look away, look away, look away Dixie land___"
3. "(This) land is your land, this land is my land, from California___"
4. "California here I come, right back where I started from. With bowers of flowers bloom in the spring___"
5. "(When it's) Spring time in the Rockies, I'll be coming back to you, Little sweetheart ___"
6. "(Let me call you) Sweetheart, I'm in love with you, Let me hear you whisper that you love me too___"
And so on. Have fun playing The Quodlibet Game. (Yeah...It might be a game just for singing nerds...)