Do you run a squid proxy? I do, and have been restarting squid to apply config changes for ages. Turns out that you can just run “service squid reload”, users have no down time and your config changes get applied. Great. Wish I had thought to check that before now….. 🙂

(This works on RHEL/CentOS, but any install of squid is capable of this via one command or another)