I only heard of 32X. It was so stupid. They came out with it then a few compatible games then it was over. It was suppose to switch the 16bit Genesis graphics to 32bits but it really was not any better. I didn't waste my money on it though.
I've heard of 3, I actually had the number 1 worst on that list (Nintendo's Virtual boy).
Got it when I was around 7 or 8 years old.
I remember getting it and my hopes being so high due to the "Virtual Boy" name tagged on to it, I thought It was going to be like being inside the game or something lol.
It ended up being terrible and I grew completely tired of it after 30 minutes, threw it away like a week later.