Elsevier offers select textbook and technical eBooks for $1 each via coupon code "ONESALE". (Select the DRM Free version on the product page.) That yields a discount of $24 to $349 off the current prices of these books, and is the best such offer we've seen. Topics include biochemistry, civil and structural engineering, computer science, psychology, and more.
Note that you can only order three at a time, but there is no limit on how many sets of three you purchase.
Amazon offers Markus Zusak's The Book Thief Kindle eBook for $2.49. That's $8 below the best price we could find for a physical copy elsewhere. A Kindle or Kindle-enabled device is required to download and read this eBook.
Amazon offers a selection of entrepreneur Kindle eBooks for free, as listed below. That's at least $99 cents off and up to $17 off. A Kindle reader, or Kindle-enabled device, is required to download and read these eBooks. The deals:
MakeUseOf offers downloads of The Unofficial, Beginner's Guide to tumblr for free. That's the lowest price we could find by $2. The file can be download as a PDF or ePub file, which is compatible with iPad, nook, Kobo, and other select eBook readers.