Four Actors You Might Not Expect to See Playing Shakespeare

Keanu Reeves--In Kenneth Branagh's 1993 film of Much Ado About Nothing, Reeves plays Don John. Don John is the villain of the piece and Reeves was fine in the role (and looked mighty fine).  Here's a brief clip of him as Don John, about to spread vile rumor about a lady.
Joss Whedon's next movie, by the way, is a modernized adaptation of the same play, with Nathan Fillion playing Dogberry. (In the Branagh film, Michael Keaton played Dogberry.)
Another unlikely Shakespearan is comedian/actor Russell Brand, who appears as Stephano in the Julie Taymor-directed production of The Tempest, with Helen Mirren as "Prospera." Stephano is part of a comic subplot involving Caliban and Brand is featured in the trailer, doing justice to the language. You can watch it here. That's Djimon Hounsou as Caliban and Alan Cumming as Trinculo.
Molly Ringwald was an uncredited Cordelia (the good daughter) in Jean-Luc Godard's 1987 sci-fi, comedy-drama mashup of KingLear, which starred Woody Allen as "Mr. Alien" and a few other big names (Julie Delpy, also uncredited, and Stage Director Peter Sellars as "William Shakespeare Junior the Fifth," which gives you an idea of just what a strange movie this was). Here's a short clip showing Molly with Burgess Meredith, playing Don Learo, her father.Five years earlier, Molly played Miranda in John Cassavetes' modernized version of The Tempest.  (Raul Julia played Kalibanos). Here's a clip from the opening of the movie featuring Molly, John Cassavetes and Gena Rowlands.
Bill Murray doesn't often get a chance to do drama but in 2000, he played Polonius in a modern-day retelling of Hamlet starring Ethan Hawke, Julia Stiles, and Liev Schrieber and Steve Zahn as Rosencrantz.  Set in modern-day New York, the movie preserved the language of the play and in this scene, Murray gives the famous "Neither a borrower nor a lender be" speech to Schrieber, who is playing his son Laertes. For me, Murray never seems natural--he never quite clicks into the conversational cadence--and the language sounds stilted. Schreiber, on the other hand, is spot on. Stiles would go on to star in a modern-day retelling of Othello (O, co-starring Mekhi Phifer.