We used Twiddla to communicate about a project that had taken a long time to develop. It was amazing how simple it was to share files and images, record video calls, add audio tracks, and annotate. I was particularly impressed with the ease with which users could collaborate without having to sign up for anything - they just put in a username and password and got access to a free hosted space. You could even use it on a mobile device if you wanted. It took us only a couple of minutes to get going and we didn't have to worry about installing any software or dealing with complicated server configurations. It was great to see a tool that was so simple and intuitive. We'll definitely use it again.