The Topic of the Day is a tough one. Of course, there is I Do! I Do!, as well as its progenitor The Fourposter, which I saw on TV in the early sixties with Jackie Cooper and Grimey Tamms. I swear I saw it, but the IMDB doesn't list it. They only list a 1964 TV version with Anne Haddy and Alistair Duncan and a Spanish miniseries. But I know I saw Jackie and Tammy do it. Hmmph!
Wiki mentions that it was done in 1955 on "Producer's Showcase", but the IMDB says in its episodes list that that was with Hume Cronyn and Jessica Tandy. btw, an impressive list of plays were done on that show, including The Skin of Our Teeth, The Petrified Forest, Darkness at Noon, Peter Pan (original Mary Martin version), The Women, Cyrano de Bergerac, Bloomer Girl... Ah, to run the the Museum of TV and Radio, or whatever it is called and spend a week sequestered there. And I'd catch Evening Primrose while I was at it.
Has anyone seen Gurney's Love Letters? It played on Broadway with a constantly rotating cast of famous actors. And as a totally irrelevant footnote, the former chairman of our math department's son is married to Gurney's daughter.
There is always Krapps Last Tape, actually one character and his younger self on tape.