It is interesting to know that there is a bag out there created in Japan which is used as a multifunctional item, like in normal circumstances it acts like a bag but when there is earthquake it will turn into a safety cushion for you.
Garppa is the name of the bag which is produced by Japanese. Probably it will fit well in their region since the rate of earthquakes is too much there. Its pretty decent bag with a lot of space in it and its bottom consist of a hard foam material known as EPS. When a situation like earthquake turns, one inverts the bag and wears it over head to protect himself from any hard material hitting directly on head. While in such situation there is a net facing you so you can easily see through that bag. Now atleast one can hope that he is carrying a safety item with him always! Now the noticeable part is that inspite having that shell inside the bottom of the bag its still folds and doesnt occupy much space. Garppa bag is available for $12 in Japan. Here is how it looks like