Last night I watched Stanley Kubrick's Lolita on TCM, which was considered un-filmable back in 1962 because of its subject matter, but isn't even as sexually explicit as your average primetime TV drama these days. I'm not sure if that's a good thing or not.
Also saw the Gregory Peck version of Moby Dick. Pretty good effects considering when it was made.
Quo Vadis about Emperor Nero and the burning of Rome. A massive film considering when it was made (1951) and still an unbelievably large production even by today's standards. Apparently they built a life size recreation of Rome that spanned 4 blocks then burned it all down. Of course, now all of that would be done in the computer. It still holds the record for the most costumes used in one film at over 32,000. I'm not sure about the historical accuracy of the events portrayed; but it was pretty entertaining.