Hi daim,
from my point of view the idea is great. I think only to store the password and not knowing the username is a good choice
There is an 'but' I can see: How to establish such a service as an unknown third party service provider.
Let me draw some examples and let me polarise deliberately.
If I have no focus on security I will not use this service because I do not have difficult or different passwords. I have my password(s) in my mind or written down somewhere. Why should I pay for a key and have to carry it with me all the time? And why only for online passwords? - To complicated for me.
If I am interested in security or secure storing of my passwords I will ask some questions, e.g.
- How liable are you as a service provider?
- How stable is your service?
- How secure is your backend service/infrastructure?
- What could happen if you loose my pairs of url and password?
- What about the risk if your service crashes or ends?
So I personaly would decide to use a standalone password store which is open source software and portable. I would be the responsible for backups or recovery possibilities and so on.
If this online password store would be optionally a solution which would be open source and I could use for myself on my server I would be easier to estimate the risk. So the decision to use it would depends on my skills but would be transparent to me.
I am sure there are enough kinds of users between these two drastic examples. I hope this could clarify my thoughts about the 'but...' I see.
Please do not misunderstand me, the idea is great and it is only my personal point of view.
Cheers,
Jens