DimDim provides a web-based platform for real-time, multimedia collaboration and meetings.
It's ideal for those that need to conference with multiple guests without having to ensure that everyone has the right software installed. Dimdim allows users to share desktops, show slides, collaborate, chat, talk and broadcast via webcam. Note that the Pro version supports up to 4 webcams and allows you to have up to 50 guests online at one time.
Once you've signed-up for a DimDim account, there are several helpful video tutorials to help you setup a meeting. Once you've set one up, all you need is the attendees e-mail addresses or you can send them a specific link that DimDim will give you. You can even pre-register your attendees from a blog courtesy of a DimDim widget.
The interface of DimDim is very well laid out although it is a bit overwhelming at first due to the fact that its designed to support conferences with large groups of attendees. While small meetings are free, pro meetings with collaboration tools for up to 50 users are available for $25 per month and webinar hosting for up to 100 users or 1000 event attendees is available for $75 per month.
Note that while you can share documents and videos easily over DimDim, the screen sharing tool doesn't work very well and if it does, tends to be very slow.
If you need to arrange an e-conference in a hurry, or want a simple way to reach as many attendees as possible, DimDim is a solid solution.