Omnivorous Surfer

If you ever need or want to edit, comment on, or fill in a PDF document...or for that matter, Word document, PowerPoint document, PNG or JPG image, or web page...then you might want to check out crocodoc. You simply upload the file, or enter the URL of a website to create a snapshot. Then you can insert comments or text, strike through or highlight text, or draw on the image. Your document will be stored by crocodoc and can be downloaded as a PDF. Additionally, you can choose to share the document for collaboration. You can view and try out crocodoc's features on the website.

crocodoc could be used by a student to highlight and annotate any text or pdf document or annotate an image or website and then email it to the teacher. Evaluating the design or content of any of the supported formats could be done by an individual or multiple individuals. I'm sure there are many other specific educational applications that others will see.