I wrote a few months ago about browsers that will be supporting the BitTorrent P2P protocol. The Opera browser has now released a beta version with this support.

A list of features according to the press release:

"- Widgets - Small Web applications (multimedia, newsfeeds, games and more) that make your desktop experience more fun. Any Web developer can create their own Widgets and share them, regardless of operating system. Try the Widgets in Opera 9 by pressing F6. Look for further development of Opera Widgets in future releases.
- BitTorrent - Instead of having to use a separate BitTorrent application for downloading large files, users can now simply click a torrent file and start the download
- Content blocker - Choose the content you want to view. Remove ads or images - it is up to you. Right-click on the Web page and choose "Block content"
- Improved rich text editing - Take advantage of rich text editing capabilities when using the latest Web mail or blogging services
- Customize your search engines - Use your favorite search engine in the search box. Right-click on the site's search field and select "Create search" from the menu
- Thumbnail preview - It's easy to have many tabs open at once in Opera. But exactly which tab had that video you wanted? hover any tab to see a thumbnail preview
- Site-specific preferences - Do you need to view a site in a different way or deny certain cookies? Want to block pop-ups on certain sites only? Site specific preferences hold the key."