>I was waiting for SSDs to get cheap enough to justify moving all my documents to a fast flash array to process and search through them faster, but that doesn't seem like it will happen anytime soon.

How much data are you working with? lol

Seems like you're doing something professional-grade if this is the case. I imagine most people, like the OP, can basically use whatever machine they have laying around and never be concerned with storage size/speed.

I'm also curious if you've tapped into cloud computing. Not that using the cloud is cheap, but I suppose if I was in a position where I'm concerned with the cost of SSDs for a processing task, then I'd be exploring all of my options and I'd be surprised if the cloud wouldn't be an "easy" solution.