As you already know that you can use the same user name and password for any Google applications, be it Gmail, Picasso, Google Map, YouTube etc. But is it safe from a security point of view? I don't think we are left with any other option, but to use the same username and password everywhere. But if it is not there, I think Google should give an option to use different username and password for each applications. Even username could be the same, but there has to be an option to choose different passwords. So, ultimately user should have the freedom to go with the same details or use separate passwords. In the current scenario if anybody happens to know your username and password, the whole world of Google is open before him. That could be a potential danger in some cases. I wonder if there is any option to keep different passwords for Google applications?