Of all the puzzles in the World, Baffleball (also known as 'Frustration Ball' in the US) made by Remco in 1969 had to be the most fiendish. Basically Baffleball was a transparent perspex ball inside which there were eight cups. A smaller ball inside the main ball was then rolled in to the first cup through a hole in its side. The idea was to rotate the Baffleball in such a way as to get the small ball to drop from one cup in to another in sequence from one cup to the next until the ball landed in number eight cup.
Sounds fairly straightforward right? Wrong. The box summed this up pretty well: "What's so hard about dropping a ball into 8 little cups? Remaining sane long enough to do it."
Although some of the cups were opposite each other, making it fairly easy to get the ball in, other cups were almost at right angles meaning that you had to get just the right twist of the ball at the right speed and inclination to flip the ball in to its destination.