Dai-Guard: An insurance company operates a large mech (called Dai-Guard) to protect things like power stations against aliens called the Heterodyne. The Heterodyne appear after earthquakes that trigger tsunamis. Dai-Guard is old and takes a lot of money to operate, so there's always bean counters who have to authorise its use -- but the three salarymen who pilot it (next to they day job of shuffling paper around) don't want to always wait for that and want to become heroes!
Tokyo Magnitude 8.0: What would happen if Tokyo was hit with a 8.0 magnitude earthquake? Two kids have to make their way from Odaiba back home in western Tokyo. The infrastructure is, of course, completely destroyed, but they walk on foot from relief station to relief station. I have reason to believe that this paints a realistic image of the disaster plans that have been prepared for exactly this situation.