We have been working on a system to send docs too but I am not sure as I don't do the sending.  But, in closing we have them sign a form regarding the non-paper docs.  Most balk at the idea of not getting paper copies.  I tell them that they don't have to print it out for review, they can review it on the computer but if you like you can.  But alas, I get "oh sure, saves you time and money but now I have to waste my paper and ink because what if my computer crashes".   Oay vay.....I give up.  Has anyone every heard of backing up your system. 

Be careful with the PDF attachments tho.  I am sure everyone is encrypting/protecting in some fashion.