A flat list of passwords works well when searching for a password. A flat list does however not solve the following management issues:
1) "How many unused discussion forum accounts did I have? Where?" or, analogously: "Do I have some webshop accounts that I used six years ago but do not use anymore, and that should be cancelled?"
2) "Let's change all my instant messaging account passwords today"
3) "Am I certainly using strong and new passwords on all my webstore accounts?"
4) "I have this easy to remember easy to break password on 37 meaningless accounts, but which ones?" (think of inverse password to sites mapping)
5) "Where is my weakest password? Or the oldest one?"
The basic need is: to quickly find an interesting subgroup of the passwords.
I am not asking more than a simple full screen four column flat password sheet grouped by icon, colour, name, site, account/login, password age or password length.
This would help me to get a one glance overview of t he totality of my accounts. It would make it easier to manage accounts (delete unneeded ones, change passwords, assess password strenght (by application), and so on).