Three codes were hidden in the PLAYING WITH FIRE post on the Investigate Ingress blog.
[1] uenuodvqse9usu5uqelyoenl
[2] mvv87orev637ms
[3] jih44wrv694ax
Code #1
Observations
Count how many characters you have, there is a reason why it’s exactly that number
Code #2
Observations
Passcode format is there, go through your usual cipher routine
Code #3
Observations
Somewhat like the last one !