http://twitter.com/ Educational social network - I am @lsadler
http://www.plurk.com/ Educational social network, more conversational based - I am @lsadler
http://www.classroom20.com/ Educators network - search for Laura Sadler
http://www.skype.com/ Video chat
http://www.tinychat.com/ Chat without registration
Google Reader Manage important blog posts
http://www.wikispaces.com/ Collaboration with students, parents, or other teachers
http://edublogs.org/ Blog
http://delicious.com/ Social bookmarking, share your bookmarks and find those that other people have shared
http://www.gcast.com/ Podcast creator