Most unintentionally funny shows of all time?

I remember as a kid watching Marcus Welby, M.D. for laughs. It was one of those shows in which every acquaintance of Dr. Welby would come down with some rare, life-threatening condition, which he would cure by the end of the episode.

Nowadays, my mother watches the Home Shopping Network channels. She doesn't buy stuff; she likes to make fun of the way the hosts gush over the cruddy, overpriced junk they sell.