Ask HN: I want to go paper-free. How?

I would love to scan all my documents and turn them into ocr'ed PDFs. However, most excellent scanners are cost prohibitive. The typical $450 is well outside my price range (college student). Most of my documents are letter-size, or odd bits of paper. I have a HP four-in-one, so I could scan them manually.

So, do you have any suggestions for software, cheaper hardware, or the ilk? Any great hacks for getting rid of the paper sprawl?