I thought this post at Obsessed With Film was good enough to repeat the link, check this out:
50 Reasons Why Ghostbusters just might be the greatest movie of all time and maybe one reason why it isn't

I wouldn't go as far in my accolades but it is a very funny spoof of science-fiction films and religions, directed by Ivan Reitman, and starring Bill Murray, Dan Akroyd, Harold Ramis, Rick Moranis,