username

Using [password] and [username] is an easy was to show the browser login dialog box
Putting [username] in a template will display the username entered into the remote browser's last Realm password dialog.

Example WebDNA code:
[showif [username]!MyLogin]
  [authenticate user]
[/showif]
[showif [password]!MyPassword]
  [authenticate password]
[/showif]
This will display the browser's regular login dialog box unless the last Realm was MyLogin:MyPassword