d represent a sizable burden for students struggling to pay tuition. Textbooks now cost much more than $100 each and sometimes more than $200 each. These high prices are driven by the cost to produce the supplemental material authors prepare for teachers and students, including CDs, quizzes, and lesson plans. E-textbooks are about half the cost of hardcopy textbooks and offer other advan- tages, as well. They are often offered as 180-day rentals at even lower costs. Moreover, e-textbooks will decrease the number of used books purchased. The National Association of College Stores estimates that used books account for one-third of total sales of college textbooks. Publishers receive no royalties on used-book sales. Another advantage of electronic formats is that they lend themselves to interac- tive features and other enhancements. For example, new tablet computers sup- port full-color and interactive graphics that students can manipulate; for instance, they can edit the inputs of pie charts and bar graphs to see how the outcome changes. In addition, publishers are thinking about other creative ways to offer information online, such as selling single chapters of books on particular topics. Publishers receive lower royalties on e-textbooks because of the lower overall prices. However, they will gain material savings on printing, warehousing, and distribution, which are major cost considerations. In addition, authors will be able to more easily edit their books for the inevitable errors that show up after a book has been printed. Some publishers allow professors to customize books for their classes by reorganizing or deleting chapters and uploading syllabuses, notes, equations, and illustrations. Textbook publishers have long been planning and implementing their online strategies. The popularity of tablet computers along with rising costs for printed books are major enablers of this trend. ONLINE COMMUNITY FORUMS Not all web activity is designed with a profit motive. Many blogs, mailing lists, and wikis are started t