patch to /bzflag/src/bzfs/commands.cxx
this will make the /say message sender's callsign anonymous to all players except admins.
anonymous /say message patch
Logged In: YES
Non-anonymity is intentional. Moving to Rejected Mods. If you want to make it an option, go ahead, that's acceptable. Default will remain public announcement.
Also note that this patch is wrong (open it in a text editor, it just changes comments)