[X-Cubed]

That's entirely dependent on what you're trying to achieve.

Sure, if you're trying to mine bitcoins, this hardware alone probably won't be much use.

But if you just want to learn about distributed systems, and how to manage a cluster of hosts and distribute tasks between them, this is a great place to start, eg: http://coen.boisestate.edu/ece/raspberry-pi/

[ris]

Right, so, playing around.

(In my experience, "learning about how to manage distributed systems..." and etcetera isn't much fun and is something you can do fairly well emulating as many systems as you'd like in software.)

[jff]

Yes, pretty much. This is coming as someone who has helped build ARM clusters. You'll spend a lot of time getting all the parts mounted in a decent way, wiring them up, getting power done properly, writing dozens of SD cards for the operating systems, and then you realize you have a cluster of 700MHz nodes with 100Mbit interconnects. You'd be better off spinning up a bunch of VMs if you want to "learn about distributed systems"