Well it seems I have already been exploring as we constructed a family tree some time ago. Geni came second in the genealogy section for the web 2.0 awards. It is a private forum for members to construct a family tree and history. Members can upload photos , add news etc. Before each persons birthday Geni sends out a reminder email so you can send the birthday person a message. Very handy as you tend to forget. You can also see your place in the family tree and who you are related to.
I think it is a well thought out site , fairly easy to use and useful to keep track of family scattered over the world.
I also had a look around this health site.
As with all these exercises you need hours to explore.