TV or not TV. That's probably a question even though I didn't end it in a question mark?

Over the years, TV shows have come and gone. Some good, some bad and most were terribly, terribly bad. What is a favorite you remember from the long ago past that you've always wondered what happened to it and why it can't be brought back since it seems Hollywood is big into recycling old crap these days. One Nick at Night should find. (Yes, I can use the web to look for mine. I just enjoy the musings.) One of my favorites when I was a kid was a program called (something to the effect of) "It's About Time, It's About Space." It was a show about a bunch of astronauts that end up in prehistoric times and join a group of really stupid cavemen. I thought it was kinda' funny and I've never seen it in reruns. So, what's your show?