Remembering of anything in a Javascript bookmarklet is a massive mistake so I would seriously doubt that Chris would make a version of SGP to do that.
You can however use your browser to save the passwords provided you are using a good browser like Google Chrome, Firefox or Opera...Safari and Internet Explorer are garbage.
Or you can use a software like LastPass to store everything for you.
Or you can to do the silly thing and only use usernames you can remember, having a different password for every website tends to be enough...plus having it hashed as well doesn't hurt.
SGP has some flaws in its design but the fact that it doesn't save anything is a HUGE asset to it.