Technorati was new to me. A giant directory of the world's blogs. I found searching, especially the advanced search, worked well, much better than the subject headings in the "directory", which I found too general to be much use.
I've now joined Technorati and have "claimed" my little blog of education resources, which I maintain in an occasional way on the Edna social networking site for Australian teachers, me.edu.au/
It's easy to find intriguing things on Technorati which you could follow up and share with other people, but blogs are also a gigantic timewaster, so I'd need to use Technorati in a very focussed way to justify it.
My little education blog is at: http://me.edu.au/b/pschindler/