I'd like to see online "textbooks" that can be bookmarked, commented upon, annotated etc. The textbooks will have animated graphics and interactive exercises inlined along with the text (i.e., the ideal that applets tried to achieve in education will be realized). You will be able to collapse and expand the textbooks to summary/comprehensive level depending on your inclination to read large amounts of text. The possibilities are endless: the texts can have pop quizzes to test your understanding, you can have collaboration built into the text where you ask your fellow students/teachers questions on sections of the text (see the Django book http://www.djangobook.com/en/2.0/ for an example). Etc.