A new tool will join the censorship circumvention arsenal this September.

Feed Over E-mail (FOE) sends restricted content, in the form of RSS feeds, via email. The tool can't help a user browse censored sites or obtain large files. But its creator, Sho Ho, says that FOE could be particularly hard to block and could work in concert with other circumvention technologies. Ho, who is a researcher with the federal government's Broadcasting Board of Governors, gave a talk about FOE yesterday at Defcon, a hacker conference that takes place annually in Las Vegas.

There are plenty of other circumvention tools out there, but it can be hard for some people to gain access to them, Ho says. Also, the makers of such tools can get drawn into a game of cat and mouse with governments that block the access points needed to make them work.

To use FOE, a user just needs access to an e-mail service hosted outside of a censoring country, and the FOE client. Information is sent via e-mail, which can come from servers all over the Web, making it hard for censors to spot a consistent source of censored information. Governments also usually don't block access to foreign mail services (there are some exceptions, such as North Korea).

FOE is different from the average feed reader in that it's able to fetch content from censored sites without requiring the user to visit those sites to set up the feed. Once FOE fetches the content, it encrypts it and sends it via e-mail much like an attached file. The user's client gets decrypts the feed once it's arrived and displays it on the local machine. Ho adds that FOE should be easy for activists to set up and maintain because it uses existing infrastructure.

The version that will be released in September works on machines running Windows, Ho says, but she hopes that volunteers will help add support for other platforms, including mobile devices.