There is a constantly-up server running on my (Uri's) PC which can be used to test the plugin:
The currently valid user name is "user" with the surprising password "pass".
Note to hackers: this is a very simple python-based server which does nothing except serving HTML pages (from the current directory; no backwards directory traversals!) and forging responses to POST requests. There is nothing to hack here…
Note to all users: The current certificate is not valid. I know that. Certificates signed by a root server usually cost money. Just click OK when you are prompted by Firefox.
Note to programmers: Use python. It's awesome.
If you want to see the anti-Phishing capabilities in action, you can connect to the following server: