"Interactive Data Visualization" is available online for free http://chimera.labs.oreilly.com/books/1230000000345
Do we need a story submitted every time O'Reilly has a ebook sale which seems like is every other day? This is nothing but an unpaid advertisement and should be down voted off the front page.
Anyone who actually is interested in being alerted on their deals probably is on their mailing list already.
Does anyone here have The Linux Programming Interface in ebook form? In the past, I've preferred to have reference style books in hard copy because there's nothing quite like thumbing through them. I've had my eye on this book for a while and at $40 it seems tempting even, as an ebook.
Informit.com (Pearson, Addison-Wesley Professional, Prentice Hall etc.) has a similar 40% to 50% off deal until January 31st:
http://www.informit.com/promotions/best-of-2013-ebook-sale-1...
This includes the ebook versions of The C++ Programming Language 4th Edition, Programming in Objective-C 6th Edition, Peopleware and several other titles.