The latest version of Opera has just been released.
Download Opera 10.1 Unite
Opera Unite enables users to share files or use their own PC as a server. You could, for example, publish a website to your hard drive, send the link to others, and they could give you feedback on it before it goes live.
You can share files by sending a link to a folder on your hard drive, and allow anyone who knows the password to download the files from it.
Similarly, you can assign another folder as an area for colleagues to send you files that are too big to attach to forums, or too confidential.
Document Courier is my file upload server. If anyone needs to send me a file I just need to send them the current password by PM.
If you already use Opera, this upgrade is recommended as it includes an important security fix. Other new features (since 9.64) include a Turbo mode (for dial-up connections), Web Fonts, HTML email, and inline spell-check (which uses Hunspell).