My friends and colleagues The Magicians built a beautiful and immersive Second Life shared space for the Strong Angel III event this year. I say "they" because my own contribution was very minor this time round. I did get a chance to tour the completed island the other day, and I made a video which may give you some idea of the place. The cheesy intro is courtesy of iMovie but the lack of sound is entirely my mistake.
You can see from the video that the build has a kind of calming idealised ancient Greek feeling, and includes several meeting areas with the ability to display video or still images. The centrepiece includes a model of the area of San Diego that Strong Angel are using for the real-world event. There are many imaginative touches; you'll see an oracle and a sheep-eating Cyclops in the video, and unfortunately only a passing glimpse of a nest of tiny dragons (I should go back and re-shoot that part). In my opinion, it's details like these that turn a potentially sterile virtual meeting room into somewhere with a real sense of being a place.
Strong Angel itself is a recurring "integrated disaster response demonstration". It allows disaster responders to get together with technologists to explore techniques and technologies that could be used in future disaster and humanitarian relief efforts. Although it will be a while before tools like Second Life can be fully integrated into that kind of response (bandwidth is pretty thin on the ground in most of these situations) the response from the other Strong Angel participants was very positive. Rather than go into that in any more detail, I'll refer you to Sanjana Hattotuwa's excellent article on the subject and to his podcast interview with Kimberly Rufer-Bach, the Magicians' Head Honcho.