"The World of Obfuscated, Esoteric, Artistic Programming" by Yusuke Endoh. A great book on art, craft, and sport of writing unusual code. Instead of treating source code as merely means to an end, this book shows all the fun and clever things you can do with the source code itself being the primary goal.
The first chapter of this book is a gallery of many of Endoh-san's code, which included programs with a wide variety of functionalities, majority of which are unusual quines. These include quines that play tic-tac-toe, quines that outputs to an image, quines that outputs QR code, quine that cycle through 99 other languages and return to its original state. The last one gained a fair amount of international publicity few years ago, around the same time when Endoh-san come to be the one who had the most number of IOCCC winning entries in the fewest number of years. All those code collected in one nicely printed book.
The remaining chapters cover specific techniques about these programs, such as incorporating ASCII art and coding under specific constraints. These include really esoteric things such as writing C code without punctuation (in a system-dependent way), and more practical topics such as using marching-squares algorithm to render graphics. Not all techniques may be widely applicable, but they are all fascinating to read.
There are also great illustrations and anecdotes spread throughout the book, starting with a quine on the inner cover (much simpler than what's printed on outer cover). The opening images to each chapter are especially great, with the sequence of title images related to constrained programming being my personal favorite. These are great intermissions to remind readers that coding should be a fun activity, a circus for both the performer and the audience to enjoy.
This book fits my niche perfectly, I haven't been looking forward to any other technical book as much as this one. I hope all engineers read this book, and appreciate how form and function go together in style. Even if they are not inclined to write esoteric code themselves, they may come to appreciate beauty in code itself.
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