Hi! I'm new here too, and I have the same question. So far I've found this comm, doctor_who, doctor_and_master, some Torchwood comms and a few scattered others than appear to have never been updated (e.g., companions). If you come across any others, let me know!

I'm not sure what the difference is between this comm and doctor_who. This one seems to be slightly more active, but I'm not sure about that, either.