Stoppard never attended college. He dropped out at age 17 due to academic boredom. Also, when Rosencrantz and Guildenstern are Dead was performed at the National Theatre in London, it made Stoppard the youngest playwright ever to have his play performed there. (Source: Bloom's Major Dramatists: Tom Stoppard, edited by Harold Bloom)
In The Simpsons episode "Tales from the Public Domain," the two characters Carl and Lenny have their names altered to Rosencarl and Guildenlenny.
The highly acclaimed Trader Joe's caramel popcorn is known as "Rosencrunch and Guildenpop." (Source)