/etc/hosts host file editor for mac osx: gasmask is an app that sits in your system tray and lets you edit the hosts file when you need, and allows for fast hot switching of profiles. Editing the /etc/hosts file on a mac isnt that difficult with commandline or your editor of choice, but it can be a bit of a pain if you have a few sets of hosts that you need access to sometimes, eg for a development environment while you are developing, and for a production environment when you are in production.
Gas Mask is an Hosts files manager.
It can modify the system Hosts file, edit various Hosts files, manage several sets, use hosts files downloaded from Internet.
You can also quickly switch to set one of them as the current Host file.