I love the GTD philosophy and recently found a solution that has dramatically reduced my inbox headaches.

Lets say I get an email that requires action. It might be a task request "Russell can you please do xyz, from a client who I am working with on a project.
From within the email window I can click on "Assign Task" and a contextual set of Manymoon task specific fields is displayed within the email (not a popup or new page). I populate the fields with the relevant information and can assign it to an existing project and thats it.

All links in the email, Google Docs, recipients everything will be included in the task and updated in my Manymoon account. Any body who is subscribed to that project sees the updates immediately.

I have written a blog about this at blog.teamspark.co.nz - I hope its of use to anybody looking for some GTD in email.

btw I am not affiliated with Manymoon in any way, I just use it.