Obscurity factor: 10
Chalk this one up to the "My Mother the Car" list of bizzare sitcom circumstances - Luke Carpenter (a very sexy Markham) is entombed in an avalanche in Alaska in 1900. He's thawed out in 1967 and found to be alive, perfectly preserved as a youthful 33 year old. He's returned to his then 67 year old son (Arthur O'Connell) and 33 year old grandson (also played by Markham) to be re-assimilated into society. Luke finds the changed world difficult to understand which leads to plenty of wacky situations.
This series was developed by Harry Ackerman, who also had a hand in Bewitched, which could account for the premis which is similar to the episodes when Sam would zap up historical figures and show them life in the 20th century. Above is part one of the episode "Little Lady X" which was the third to air in the series. It was uploaded to YouTube by 2nicks.
Obscurity factor: 10 (infrequently aired, not on DVD, would be forgotten if not for YouTube)