I have been studying GA ever since first hearing about it 10 years ago. David Hestenes book, "New Foundations for Classical Mechanics" was my first foray followed by "Geometric Algebra for Physicists" by Doran and Lasenby, however lately I have been focusing a on GA for computer graphics instead of physics. I am working through Euclid's Elements in parallel.
I love the work of Pablo Colapinto (wolftype) [1]. He created a C++ library for GA, and somebody made the library for JS. His academic papers are inspiring and clear. He also has some really good Vimeo videos showcasing his work under Wolftype.
The history of GA is a solid example of how it is not always the best idea that takes hold. Gibbs and vectors and quaternions became the way.
The history of GA is a solid example of how it is not always the best idea that takes hold. Gibbs and vectors and quaternions became the way.