HTTPS Everywhere is a Firefox extension produced as a collaboration between The Tor Project and the Electronic Frontier Foundation. It encrypts your communications with a number of major websites.
Many sites on the web offer some limited support for encryption over HTTPS, but make it difficult to use. For instance, they may default to unencrypted HTTP, or fill encrypted pages with links that go back to the unencrypted site.
The HTTPS Everywhere extension fixes these problems by rewriting all requests to these sites to HTTPS. Note that some of those sites still include a lot of content from third party domains that is not available over HTTPS. As always, if the browser's lock icon is broken or carries an exclamation mark, you may remain vulnerable to some adversaries that use active attacks or traffic analysis. However, the effort required to monitor your browsing should still be usefully increased.
What's new in this version:
This is the first version on CNET Downloads.