Swartz’s Last Gift, the Invasion of the Androids & More…

... can be seen at its GitHub project site 'deaddrop / deaddrop' found at https://github.com/deaddrop/deaddrop

The DeadDrop code itself is fully open-sourced, while Strongbox is apparently more of The New Yorker's proprietary implementation of DeadDrop. The New Yorker Strongbox link is http://www.newyorker.com/strongbox/ and here is its privacy policy, current as of Wed 15 May 2013 1:41:40 PM EDT:

Quoting:Our privacy promise

The New Yorker's Strongbox is designed to let you communicate with our writers and editors with greater anonymity and security than afforded by conventional e-mail.

When you visit or use our public Strongbox server at http://tnysbtbxsf356hiy.onion , The New Yorker and our parent company, Condé Nast, will not record your I.P. address or information about your browser, computer, or operating system, nor will we embed third-party content or deliver cookies to your browser.

Strongbox servers are under the physical control of The New Yorker and Condé Nast in a physically and logically segregated area at a secure data center. Strongbox servers and network share no elements in common with The New Yorker or Condé Nast infrastructure.

Strongbox is designed to be accessed only through a “hidden service” on the Tor anonymity network, which is set up to conceal both your online and physical location from us and to offer full end-to-end encryption for your communications with us. This provides a higher level of security and anonymity in your communication with us than afforded by standard e-mail or unencrypted Web forms. Strongbox does not provide perfect security. Among other risks, if you share your unique code name, or if your computer is compromised, any activities, including communications through Strongbox, should be considered compromised as well.

The system is provided on an “as is” basis, with no warranties or representations, and any use of it is at the user's own risk.

The link to the Tor Online Anonymity Project is https://www.torproject.org/ and is separate from The New Yorker's own Strongbox application.