I don't know whether you have seen this website before, but it lists mistakes which have been spotted in films and is quite interesting.
CLICK HERE The link takes you directly to the top 20 most mistake-filled movies. The Matrix is number 1 with 177 mistakes, Titanic number 2 with 150 and Lord of the Rings number 3 with 141 mistakes. To see what the mistakes are, just click on the title of the film. To see the mistakes in any other films, just click on All films and then on the start letter of the title.