@groguard designed the Giant Board which runs Linux in the form factor of the Adafruit Feather:

The Giant Board is a super tiny single-board computer based on the Adafruit Feather form factor. We always want more power in a smaller package and the Giant Board delivers!

There are always those couple of projects that just need a little more power, or a different software stack. With the release of the ATSAMA5D27C-D1G, its made linux possible in such a small form factor. Listed below are the specs and current pinout of the board.