This board is a very convenient way (maybe the most convenient one I've seen) to setup a bare-metal cluster of computers. Not just multiple cores, not just multiple VMs, four entirely separate ARM computers communicating over a real hardware network. One Alternative to boards like this is to connect multiple SBCs together, with all the wiring, and also some mechanical support. Another (more powerful alternative) is to install some kind of server rack at home. More expensive, too. Using multiple virtual machines is also not quite the same.
What people use it for? Mostly to learn how to deal with problems that arise from managing a cluster and running software on it. Can you build a website that tolerates getting one of the nodes or hard drives turned off?
Some people use such solutions for productive things, like a Home Server, but a store-bought NAS or a single PC is usually more performant. A PI cluster might be less power hungry in some scenarios.
Some people use them as build/test platforms for code that should run on ARM architectures. Others have used them to host a website from their internet connection (I know...).
Some people just have fun tinkering with such things....
What people use it for? Mostly to learn how to deal with problems that arise from managing a cluster and running software on it. Can you build a website that tolerates getting one of the nodes or hard drives turned off?
Some people use such solutions for productive things, like a Home Server, but a store-bought NAS or a single PC is usually more performant. A PI cluster might be less power hungry in some scenarios.
Some people use them as build/test platforms for code that should run on ARM architectures. Others have used them to host a website from their internet connection (I know...).
Some people just have fun tinkering with such things....