Have been on the lookout for a desktop videoconferencing tool to use for groups of 10 - 15 teachers scattered around the country. I have known of DimDim for a few months now, and though I have recommended that some of my students check out it's feature set as part of their project on emerging technologies, to be honest I hadn't taken the time to check it out myself. Until last night, that is.
At first glance, DimDim looks just what I am looking for. It's free for up to 20 users, and has plenty of low cost alternatives if you need to go further than that. It is entirely web-based, so no downloads and the like. Last night I shared a 12 page PDF file with my test buddy, and even without using a headset and microphone, communication was OK - though I'll use them next time.
DimDim looks to have all of the usual features (whiteboard, chat, desktop, web and slide options), so at this stage I'm reasonably impressed. We'll give it another once over from school next week, but at this stage it looks like it could be a goer for our application. If you are on the lookout for a videoconferencing tool, check it out.