Web 2.0 Tools in the Classroom

As the tools of the Web 2.0 concept have become more of a reality in classrooms than ever before, I am interested in knowing some of the "so called" tools that are being used by teachers. I plan to incorporate blogging into many of my classrooms throughout the district this year. I also am interested in weaning individuals away from computer specific bookmarking. I will be pushing tools like del.icio.us. I am interested in podcasting and opening other doors of communication using audio and audio video skype connections. I've grown over the years from using FTP to now using some of the tools in Microsoft's SharePoint Services for file sharing. We will also begin to use this tool much more for Online Collaboration among students and among administrators in the district. I AM LOOKING for other thoughts on Classroom usages of these tools and many others that I have not mentioned here.