Aimed primarily at journalists, bloggers and activists, Privacybox is a free service from the German Privacy Foundation, it provides a way to anonymously exchange messages with others without the possibility of anyone tracking down the sender.
If your friend’s computer is seized or stolen and its hard disk looked into there will be nothing linking him to you other than the message contents, Privacybox can be compared to an online dropbox point where you simple drop the messages, including attachments (600Kb) with pictures or documents and it is anonymously forwarded to your contact, all you need to know before sending a message it is their personal contact URL.
Privacybox contact methods
When you create an account with Privacybox you will automatically be assigned four URLs, you can use any of them and pass it on to your contacts, or post it online.
Tor hidden service: A tor hidden service URL website in the form of .onion, only accessible for people using tor and not to the general Internet populace, anyone sending you messages using this URL will be protected by the tor proxy.
I2P anonymous network: You are assigned a .i2p URL, it is only accessible for people using the anonymous I2P network, an anonymous network that encrypts data and distributes it routing traffic through other peers.
Mobile device access: You will be assigned a .mobi URL for your people to contact you suing a mobile device.
Desktop computer access: You will be given a plain vanilla URL to be access through the normal Internet, this URL; like the others can be posted anywhere, forums, websites, etc.
The sender decides which is the best form to contact you, as long as they have your personal URL, which is not known to anyone unless you reveal it, you can create new contact URL and change your encryption keys anytime you like using Privacybox account management.
Retrieving anonymous messages
Anonymous messages and attachments can be retrieved using the German Privacy Foundation POP3 free SSL postbox, you can find the settings for this inside your Privacybox account, you can use a tor hidden service to receive the email, have the messages forwarded to an I2P mail account (without S/MIME encryption) or have the anonymous messages forwarded to an external email address, the message headers will not contain any identifiable information.
In your account settings you can choose no encryption, S/MIME encryption, and PGP encryption, in order for encryption to take place (optional) you will have to supply your own OpenPGP public encryption key or a S/MIME digital certificate (in .pem format)
Interface is multilingual, available in English, German, French, Russian and Portuguese, for questions you can contact the admin team using their online form, PrivacyBox software is open source.
Message deletion and logging
Privacybox claims it does not log any data about the sender of messages and can’t provide any information about it even if compelled, it is impossible to supply what does not exist, however, because the system is open to abuse due to its anonymity, if abuse is reported to them the account will be deleted.
There is no reply function, PrivacyBox is a one way anonymous messaging system.You can erase your Privacybox account any time you like by entering your password in your account, all of the data is then erased straight away and the data backup vanishes one hour after that.
UPDATE 2013: Product has been discontinued.