Protecting database passwords

Hi there, I wrote a php script that accesses a database, and I am wondering about securing the password to the database. I could prompt the user for the password every session, but I don't necessarily want the user to have the password. Unless I'm missing something, any on-disk place I store the password needs to be readable by PHP, and therefore isn't very secure. I have restricted the rights of the database user, but I'm wondering how others have dealt with this, or maybe I'm completely missing the point. -Bob