Nice.

You can ask people directly if there is something that you can't find online or you don't know how to find. Though, GNU Social's DM system/Message does not seem to be reliable.

Wireshark is also your good friend. Most of the time it is enough by filtering DNS requests (assume the programs that you suspect make DNS requests).

The people that care about privacy, even among *nix users, are only a minority. I think I'm gonna write a rant on this soon...