I've seen 'Duel'....it's 70's I think and it's Steven Spielberg's first movie. Is this the one you're talking about? I wouldn't say it's 'funny' but it is trippy and maybe funny in a scary/creepy/strange way! It's about that big Semi truck bearing down on this poor little car for hundreds of miles...you know how the front of those Semi's can look like faces...well it has an ominous presence!