I have very little paper moving around in my system, but it's difficult to get rid of all of it. Here's what I use:
My bag has just three things in it most days: an iPad, the Davidco folder set and a Levenger circa notebook.
I use Evernote for digital reference.
I use Simplenotes for project support notes.
I use Mindnode for mind maps.
I take pictures of documents with my iPhone. There are several programs that do useful things with such documents, but you can also use the stock photo app. This has been particularly handy in dealing with elderly parent issues. The US health care system- need I say more?
I try to keep email as simple as possible: extract useful data as it comes in, and one big archive folder per year.
I use Dropbox to sync files everywhere.
I've chosen an all-Apple approach that works well for me. You may be constrained by company policy and by mandated company hardware and software.