[bane]

I'd point out that modern SSDs are getting within the an order of magnitude of RAM in terms of speed. If your dataset is larger than what can fit in RAM, you can probably come up with some kind of on-disk storage mechanism, at the cost of speed. Buy a few and RAID them and you can probably get even closer.

Still not 1000 machines, but one cost in this scenario is that you also won't have to pay for the humans to run the network the 1000 machines live on, or the power for 999 machines, or the cooling, or the floorspace, etc.

"RAM is for the stack and SSDs are for heap" is a phrase I'm starting to hear.