There is no strict definition of unconventional computing. Being an unconventional computist is not a matter of training but thinking and living. Phenomenologically most works on unconventional computing are about implementation of computing in novel substrates (chemical, physical, biological), development of computing schemes and algorithms not fitting into the mainstream framework, or designing of computing architectures inspired by chemical or biological systems. This short book gives a snapshot of the unconventional computing field. The world-leading experts in the unconventional computing author all articles of the issue. The topics include analog computation, sensing and computing with fungi, chemical computing, swarms of minimalist agents, computational universality, mega-computing in the universe, information and music, universal sensing, art of deduction, reversible computing, philosophy of machine learning, epistemic incompleteness, post-quantum unconventional computing, complexity of natural computing, arts and cellular automata. Articles presented are punchy and well illustrated. All articles are short and self-contained. The book will serve well as a light-touch introduction to unconventional computing for people not familiar with computing and might inspire artists and humanitarians to enter the field.