Holy long-lived threads, Batman! This will be by my count the fourth time I have contributed, and I just read from my last submittal to the end to make sure these were not yet mentioned:
Joe Versus the Volcano - Yes it does star that most famous modern romantic comedy pair, Meg Ryan and Tom Hanks. But to my mind, this movie is better than any of their other pairings. In addition to comedy, it has great music: Eric Burdon's version of Sixteen Tons, Elvis Presley's Blue Moon, Good Lovin' by the Young Rascals, and a Spanish version of On the Street Where You Live from the musical My Fair Lady. It also has an unremitting existentialist plot, and is sprinkled with gemlike cameo appearances by the likes of Lloyd Bridges (the obsessed billionaire), Robert Stack (the Doctor), and Barry McGovern (the luggage salesman). After bombing at the Box Office, now a definate cult film, but unseen by many.
The Collector (1965) - From the John Fowles novel of the same name, the dark tale of a Butterfly Collector who is so socially inept that he cannot talk to women - so he collects them as he does butterflies. A great early feature film appearance by British character actor Terence Stamp that would earn him a lifetime career playing heavies and villians. Samantha Eggar at her most seductive age is his first victim.
The Lost Battalion (2001) - A feature length, made-for cable (A&E), historicly accurate, and well-acted war movie set in the closing weeks of WW1. Rick Schroder stars as Major Charles Whittlesey, who leads 500 American men into the Argonne Forest in Winter. It is a time when battles are fought with machine guns, airplanes, tanks, and accurate artillary - but communications still depends upon carrier pigeons - which are routinely shot at by both sides. Whittlesey and his men are behind the German lines, surrounded, they have little ammunition or supplies, and are being shelled by both sides - but they will not surrender during a 5 day battle.
Hopscotch - A little known comedy starring Walter Matthau in one of his best roles. The supportting cast includes Sam Waterston, Glenda Jackson, and Ned Beatty. "The Most Dangerous Man in the World" is publishing his memoirs, exposing the CIA, the KGB, and the FBI. He'll have to be smarter than all of them to survive. He is - and it's very funny.
Stealing Beauty (1996) - One of the wife's favorites, and seemingly not very well known. Not a bad story if the female in your life insists upon viewing a film with you - and it does include a lengthy topless scene with the 19-year-old Liv Tyler, who is on a quest to find her Father and lose her virginity, all in one vacation at an Italian country villa.