There's Something About Mary (1998)

There's Something About Mary was a groundbreaking comedy when it came out in 1998.  I remember seeing it in the theatre when I was in high school and laughing through most of the movie.  I recently watched this comedy classic again, and I enjoyed the film so much.  Ben Stiller plays a guy who wonders what happened to his high school crush, Mary, played by Cameron Diaz.  He hires Matt Dillon to spy on her, and Dillon instantly falls in love with Mary and pursues her himself.  The film is full of raunchy humor, like the scenes from prom, the old woman who rooms with Mary, and the crazy dog on various meds.  I forgot all about the famous scene where Mary borrows some "hair gel."  There were so many comedic gems throughout the film.  It is a classic that stays funny with time.
It gets 4 out of 5 stars.