A - I have access to quite a few *nix servers, where multiple login users and/or services with district UIDs are a thing. B - Not sure how practical most of th

A - I have access to quite a few *nix servers, where multiple login users and/or services with district UIDs are a thing. B - Not sure how practical most of this is yet, but there's cool stuff around isolating individual programs even on single-user machines. C - My desktop has a couple things that listen on the network, and it's nice that they only have access to specific things.