For those of you who may have missed an EDge21 featured post or who didn't have the opportunity to look at some of them during this past week, here's a second chance.
Presefy is a just-out-of-beta web service which allows you to store and control your presentations anywhere you are. All your presentations are available and can be controlled via an Internet connection.
Widbook is an intelligent platform where authors and readers have the opportunity to share their best digital content with people worldwide.
GradeMark saves time and improves feedback through an online grading system where standard and customized annotations appear directly on the student's paper.
Science NetLinks is a K-12 science education resource where you'll find teaching tools, interactives, podcasts, and hands-on activities, and all free.