I love funny movies. I am not a big fan of the corny movies or the comedies that are predictable. I like the one-liners that sneak up out of nowhere and smack you in the face with laughter. It takes a little more brain power to "get" the joke but at least you feel like you are being a part of the movie watching experience.
That's why I'm recommending 'Murder by Death'. It has a wonderful cast including Peter Falk, Truman Capote, David Niven, and Peter Sellers. The film came out in 1976 with the tagline "By the time the world's greatest detectives figure out whodunnit... you could die laughing!" And the tagline is true. This is one of the few films that had me laughing out loud.
So, if you are looking for a comedy/crime/mystery movie that is done well and will have you laughing at a clever screenplay I highly suggest 'Murder by Death'.