Humble Bundle offers downloads of its Humble Learn Raspberry Pi and Arduino eBook Bundle for whatever you want to pay. If you opt to pay the bare minimum of $1, you'll get Make: Raspberry Pi and AVR Projects, MintDuino: Building an Arduino-compatible Breadboard Microcontroller, Make: Getting Started with Adafruit Trinket, Make: Getting Started with Adafruit FLORA, Make: Making Simple Robots, and Make: Arduino Bots and Gadgets. That's $57 under the lowest price we could find for universally-compatible digital copies of these books elsewhere. They're available in PDF, ePUB, and MOBI formats. Coupons for $10 off print and $5 off digital Make magazine subscriptions are also included.

If you pay more than the average, currently $13.26, you'll also get Make: A Raspberry Pi-Controlled Robot, Make 38: High-Tech DIY, Make 36: Boards and Microcontrollers, Make: The Maker’s Manual, Make: JavaScript Robotics; Make: Getting Started with Sensors, Make: Getting Started with Arduino 3rd Edition, Make: Getting Started with Raspberry Pi 2nd Edition, and Make: AVR Programming. Finally, pay $15 or more to bag Making Things Talk and Make: Sensors. The total value of these books combined is $270. Deal ends December 16.