"software design for flexibility" by chris hanson and gerald jay sussman will be out in 8 days.
all the e-books i can find for it have drm applied which would usually rule out a purchase for me. but, i can make an exception in this case because the text is going to be creative commons-licensed, just like sicp!
(i even double-checked with author chris hanson, who was kind enough to reply to an internet rando's email!)
@pho4cexa I checked with Gerry Sussman a few months ago as well and he too confirmed that it would be out under a creative commons license.