Kind of related, but does anyone have good software for dealing with PDFs? Any important letters (or something I may want to refer back to later) I scan and em

Kind of related, but does anyone have good software for dealing with PDFs? Any important letters (or something I may want to refer back to later) I scan and email to myself. I used Evernote previously, the nice part is it OCRs the PDF so I can search text within them, but the workflow isn't that nice (and I'd prefer something self-hosted). When I've asked before I've received recommendations for full blown enterprise document management systems, but all I want is something with an interface like Gmail for PDFs (I'm suprised Google themselves don't do this within Gmail).