Has anyone ever been on the same gameshow twice?

Answer 1

It can happen, depending on the show. For example, on The Price is Right, you can be on the show again after 10 years, and there have been contestants who have appeared on the show twice. On the other side of the spectrum, there was a contestant on Jeopardy! who appeared twice, and had his winnings withheld due to the show's rules saying that you can't appear again if you've already appeared once on the current version of the show (note that contestants that have appeared on the Art Fleming version of the show can appear again on the current version, and it's happened before).