My undergrad math professor created one of the first fully online linear algebra texts: http://linear.ups.edu/html/fcla.html It's integrated with Sage, a Python library for studying (among other things) number theory. Another prof at the same university also wrote his own linear book, using a lot more illustrations, but as a traditional textbook.
I see this book as a solid evolution in both directions. Nicely done!
I see this book as a solid evolution in both directions. Nicely done!