I mentioned earlier in the year I am focusing on reducing the overall amount of traffic in my inbox, and at the same time the amount of time spent managing my inbox. In my work life IBM Connections Files has greatly reduced the number of attachments received in email, and the ones I do receive are simply dragged and dropped into Files using the Notes Sidebar plugin.
In my personal life no such luck, I still get quite a deal of attachments in email, and I have found a pretty good system for dealing with them using a combination of Gmail, attachments.me, and Dropbox.
Using rules in attachments.me I have automated some common scenarios where I receive attachments, and have them automatically saved to Dropbox. For example in the rules below in the first I have identified a couple of frequent senders of documents, which are saved straight to Dropbox where I can simply open them (and rarely do I have to go back and open the original email). The second rule is even simpler when my Mom sends me a picture it is automatically saved to the appropriate dropbox folder.
Attachments.me also supports integration with Box, Skydrive, and Google Drive.