Yesterday it was not my day, still I could pick up some informations.
Trackbacks are rather useful to comment other people s postings and to get comments to my postings. So it is possible to exchange informations, to stock up your knowledge in any topics. At the same time you are always informed about the meaning ot the one I am commuicating with.

RSS I could imagine using it with my pupils. I can ask them to get informations from different links to imolanate new informations, for example during a newspaper projekt they should find the daily headlines in some papers.
All the informations they can share with the other users.

I believe that is all I can remember.