College E-books?

I'm finishing up my master's degree through the University of Maryland, where it feels like I've been in school for my entire life. Books are incredibly expensive, although for my master's in business it hasn't been nearly as costly as my undergraduate degrees, one of which was in Art History. Those enormous books with lots of glossy photos of paintings were hundreds of dollars a piece. In the past I had always purchased used books from Half.com or Amazon because I could conserve natural resources and my money at the same time. However, this semester I had a new option, E-books. I was a bit nervous at first because having a book means that you can take it with you anywhere and you can highlight all over it, which I do excessively. The cost of the e-book was significantly less, however, and I couldn't find it used. I purchased my book through our college bookstore which gave me access to a book offered by CourseSmart. I've been using it for about four weeks now and well, it's not so bad. I can highlight electronically and it keeps the highlighting until I choose to remove it. I can make notes and I chose the internet accesbile version. You can download a drm version as well, but then you can only access it from one computer. I work from my daughter's computer, my work laptop, and my husband's mac and I really enjoy the flexibility. There area few downsides to e-books though, including the fact that it wears my eyes out very quickly, I can only choose from two zoom settings, and there is no way to save your page. However, I imagine that eventually the software will progress to include some of these additional "needs". Their website boasts that they have saved over 175,000 trees so far, so I feel good about conserving the environment, and my cashflow. Now I'm off to do some exciting reading on finance in my e-book online. I only hope I can remember what page I was on...