I think there is a market for it, The other poster does have a point though, it is a single point of failure, from your site being compromised, point of view. Y

I think there is a market for it, The other poster does have a point though, it is a single point of failure, from your site being compromised, point of view. You would have to think very hard about security, like a 2 phased strategy or something like that, where all the passwords are stored encrypted and your services does not have the key, the lock-down code, could be the key that the user provides, to unencrypted the passwords and site url's they go to. The other option would be to make it a client side app, where they store the passwords locally and are responsible for their own security. I don't know what your market looks like in terms of pay or free, I know I would not pay for it, but I am not many peoples target market. I usually an outlier when it comes to user demographics.