MarsEdit automatically detects settings. I simply told it the URL for V, http://visforvoltage.org/, and it autodetected that this is a Drupal site. The only change to make is in the Settings dialog to change "Blog Id" from "1" to "blog". Then you can log in using MarsEdit and your V user ID and password.
This should work with other blog editors. On Windoze a popular one is named w.bloggar IIRC.