Any format can perform this feature, but it fits best on a station that plays more library material, or has older listeners who like to get nostalgic. Time Machine is exactly what it sounds like, a throwback feature that takes listeners back to another time.
NBC-TV show Dateline plays this game effectively, and is a good example of how to do it well. They do a great job luring their audience through commercials to pay off on the other side. No prizes are needed!