People who don't broadcast their IP address? At https://bitcoin.stackexchange.com/a/9807/5228 Tom van der Woerdt wrote "people who don't broadcast their IP address".

What did he mean by that? Is there a way to set up a particular Bitcoin client so that it does not broadcast my IP address or to make it more private in other ways?
Sure. Install Tor and add tor=1 to your bitcoin.conf.