If you need to change your password, please use the password reset form, which will send you an email and let you set a new password.
To change the email address associated with your account, send a short request to us at firstname.lastname@example.org and we'll get it done for you. We know that should be an automated, in-account thing - we haven't done that yet, so it's a little manual for now.
To close your account, please just send us an email: email@example.com
Don't worry, there won't be any hard sell, we just haven't automated account closure yet.