The movie "Gone Fishin'" Joe Peschi drives a blue 68 Barracuda fastback throughout the movie.
"The Mad Room" from 1968 has a new red 68 Barracuda convertible in a couple brief scenes.
"Set This Town on Fire" a movie from 1969 has a red 69 Barracuda convertible in a few scenes as a main character's car.
"Ten Things I hate about You" has a 64 Dart GT as a main character's car.
In the movie "Fireball 500", Frankie Avalon drives a 66 Barracuda customized by George Barris.
A 64 Barracuda is used in a chase scene in the movie, "Slaughter"
A 68 Barracuda Formula S fastback was used in an episode of "The Protectors".
http://www.imcdb.org/vehicle_37377-Plymouth-Barracuda-1968.html
Since much of the series was filmed in Spain and the '66 Dart sedans were built there into the 70's, there are several episodes with 66 Darts in them.
Heres a link to the opening sequence of the Doris Day Show showing her driving her 69 Barracuda convertible.
[ame="http://www.youtube.com/watch?v=m6J2ZUJ1Auc&feature=related"]YouTube - The Doris Day Show (Season 2): Opening Credits[/ame]
My Favorite Episode of Mannix was "Pressure Point" from season 2. Mannix jumps out of his Dart convertible and into a girl's 68 Satellite convertible, and they are chased by a 67 Barracuda Formula S convertible.
http://www.mefeedia.com/watch/32572492