I am preparing a short presentation for Kentucky school district technology coordinators on the "10 Best Web 2.0 Tools for Education". I am looking at several "best of" lists out there (e.g. Jane Hart's 25 Tools, http://c4lpt.co.uk/25Tools/index.html
) but would love suggestions from the folks here on Classroom 2.0.
So, what Web 2.0 tools or services do you think every educator should be familiar with and why?