TreeHugger shows a lot of lovely projects with what readers consider to be dangerous stairs that don't meet building codes. One of the great benefits of being an architect in the midcentury modern era is that the codes were a lot looser, if they existed at all. People didn't sue so much, and took a bit more personal responsibility. Kids had a lot more freedom (I remember climbing out windows and sitting on the roof, being on bouncy boats without lifejackets, etc). David Frum points to an interesting post by Clare at Projectiphile, which lists 15 Mid-Century Modern Dream Homes that will Kill Your Children. Of the photo above, she notes "It is pretty certain that none of these children reached adulthood intact."
See more examples at Projectophile