Punkey on Backpack and GTD
Punkey at What's the next action has a great post on Backpack and GTD.
I also use Backpack as part of my gtd implementation and find it great. What I find most frustrating with Backpack is however the absence of a calendering function. The best way I have found around it is to also use Airset and have an iframe of the calendar on the homepage of my Backpack account.
Punkey expresses the view that "The predefined mailadresses are a pain to remember. This should be something like firstname.lastname@example.org instead of the random names you get now."
What I do to go round the problem is to enter each backpack email address as a contact in on my email account.
For instance the @Office page is entered as
First name: Office
This therefore give something like "Backpack, Office" in my contact list.
This way there is no need to remember each Backpack page email address. I found Backpack extremelly useful to process my email in-box and to easily forward emails to the relevant Backpack page, easily transforming every email which warranties it in a next action item.