Some time ago I moved from my utilitarian igoogle page to a new RSS startpage. When choosing a platform I'd wavered between pageflakes and netvibes sites - there seems to be little difference in the two. Both provide a sleek ajax-based page with options for adding a variety of embedded media and updated feeds.
After using each of the sites I'd hoped to offer a technology workshop on organizing webcontent with these start pages. I eventually chose pageflakes as the subject of the workshop, because I found pageflakes seemed to work a little better with our district's webfilter. There is also ateacher pageflakes site that makes it even easier to set up a page with education in mind.
I held the first workshop over spring break, and I really think pageflakes could play a role in helping teachers by providing content to help teach units. Teacher could use the site in the way I use the site - mostly to organize my RSS feeds from sites and blogs I check most frequently. But teachers might also create pages that contain content for their classes or even each separate unit they are teaching. Pages can be published, through pagecasting, which can allow the page to be accessible from any computer connected to the Internet. Teachers could use the pages during instruction, and students could access the sites and media the teacher chooses for a lesson.
Pretty great, and as is often the case with much of the new tech stuff I like, it's free and web-based so no installation is necessary.