Rating EverNote as the best web, pc (client) and getting better for all the mobile devices and platforms. I think its just amazing! After a year or so, I can 't live without it.
I keep everything in it, from scans of important and non important documents, articles on the web, selected info for reference later, pictures of anything, to pdf's.
Even in the free version if OCR's your jpg's - EVEN handwriting - pretty neat.
One of the first things I scanned in to test, was the handwritten invoice for some work on my car. A year later I was able to find it via a search - and found an error! Previously, even if I save the invoice, i wouldn't have or couldn; t have found it - but evernote did.
Many users are using it instead of MS Onenote.