Quotes
Dean Winchester: We know a little about a lot of things; just enough to make us dangerous.
Trivia
With the exception of season 1 every season finale starts with the song "Carry on My Wayward Son" by Kansas. In season 1 the song was used in the second to last episode which was part one of a two part finale. See more...
Movie Mistakes blog
Popular blog posts:
Top 15 biggest Harry Potter film mistakes
30 Biggest mistakes in the Star Wars movies
The 10 biggest mistakes in Iron Man 1 & 2
Other great sites
I'm afraid there aren't any mistakes listed for the show as a whole - please use the links above to narrow your search.