While we've covered the converting warehouses into high-tech graveyards.before, what we have in the U.S. is nothing compared with the Japanese. Since burials in Tokyo can be so expensive (topping out at more than $100,000), some people have invented a more conservative yet radical solution, according to the BBC:
Instead of one grave per a given area (like a house on a plot), the graves are stacked (like condos) several feet high. To give relatives access to the remains, a robotic arm retrieves the urn (most Japanese are cremated) and shuttles it to a "mourning room." Think of how a jukebox retrieves a record, only it's ashes.
It's a novel concept, but it's also uniquely Japanese, and we can't really see that catching on here. But it totally makes sense in hyper-dense Tokyo where land is scarce and getting out of the city really isn't an option for many people.