- Yellowbrick — Open source visual analysis and diagnostic tools to facilitate machine learning model selection.
- Eight Habits of Expert Software Designers: An Illustrated Guide — Experts imagine how a design will work—simulating aspects of the envisioned software and how the different parts of the design support a variety of scenarios. When working with others, experts regularly walk through a design by verbalizing its operation step by step. When alone, they simulate mentally, exercising the design repeatedly over time. This fits with my sense of good programmers as good simulators.
- ImagePlay — A rapid prototyping tool for building and testing image processing algorithms. It comes with a variety of over 70 individual image processors that can be combined into complex process chains. ImagePlay is completely open source and can be built for Windows, Mac, and Linux.
- Rockbox — A free replacement firmware for digital music players. It runs on a wide range of players.