Team Near Space Circus sent 7 Raspberry Pis up into near space using a high altitude balloon. I previously covered the rough layout of their spherical shaped payload here and now the team has published another blog post about the project. This time, they cover the networking part of the payload. This was achieved by hooking up the TX/RX pins of each Pi to the others in a formation known as ‘token ring’. This is a very old way of doing networking, of course, but it is still a valid concept. Read Francois Dion’s blog post for more information.