The coin trick that Henry Winkler does in the movie is something the actor does in real life. During public appearances, Winkler will often do the trick for children.
In 1995, R.L. Stine wrote a very similar story in his "Tales To Give You Goosebumps", with almost the same plot and set-up, even down to the title, "Click". Scholastic, Inc. almost sued Adam Sandler and this film's producers for plagiarism. Both parties agreed the entire situation was a coincidence, so no legal action was ever taken. Both stories could easily be based on the old French tale "The Magic Thread", in which a boy is able to pull a thread to speed up the parts of his life he doesn't like. He quickly finds himself an old man before being given a second chance.
The little girl at the lakeside during young Michael's flashback is Kate Beckinsale's daughter, Lily Mo Sheen.
The neighbors in the film are named the O'Doyles, which is also the name of the family of bullies who always say "O'Doyle Rules" in Adam Sandler's film Billy Madison (1995).
As an in-joke, the names of some of the crew members are visible on a few headstones at the graveyard scene near the end of the film.
Dolores O'Riordan, The Cranberries: Cameo: Dolores O'Riordan of the Cranberries, the singer who sings the band's song "Linger".
Frank Coraci: as the nurse who attempts to sedate Michael in the hospital, but sedates himself instead.