A login box is a couple of text fields and a button. A ten-minute job, right? Well, coding the first version probably is, but does it work? Easy - fire up the browser, enter a username and password and click Submit - Success!! Really? Did it set the cookie or was it set from my last test? OK, try again. Clear my cookies, log in again, and ... it fails! Oh! I'm already logged in - OK, clear the cookies, clear the database session, log in, and check the cookies.