Movie Recommendation

I just watched this movie from 1980, a comedy called "Simon". It stars Alan Arkin as a disguntled professor of psychology who is taken to the government funded "Institute of Advanced Concepts" and made to believe that he is an extraterrestrial. It's the funniest comedy I've seen in a while, but then my sense of comedy can be a little strange. If you're interested in the movie, I'd imagine it's sufficiently old that your public library system would be more likely to have a copy than a video rental place.