Indie games studios, what tools do you use these days?

Indie games studios - both large and small - working with fully-remote team members, what are the daily tools that you are using in these times of "distributed collaboration"? How did you adapt your studios/businesses to the new remote working model? I am more interested towards the workflows between artists and developers and the administrative part (project boards, planning, etc.). More like "how are you doing it?" instead of "what are you using specifically?". It seems that some of the "established" methods keep working, but some need new approaches. What's your "secret" (that you can share with the world)?