Giant balloons that you can ride in. How is that not just the greatest idea ever? Zee Germans thought so, at least, and back in 1934, they sent the 776-foot-long LZ 127 Graf Zeppelin on a little jaunt across the Atlantic from Europe to Rio. It was not entirely smooth sailing, and some in-flight repairs were required, which involved some dudes going up on top of the zeppelin, climbing down its sides on ropes, and fixing stuff.