There's a glitch with this app in Lion. Whenever I edit the hosts file outside of using Gas Mask (doing it manually, basically), when I open Gas Mask, it doesn't show the newly added information to the hosts file in Gas Mask... no matter how many times I re-open the app. However, once I delete the Gas Mask preferences file and re-launch the app... it shows everything that was added to the hosts file. Every time I edit the hosts file manually, I have to delete the Gas Mask preferences file in order for it to display the information correctly. It works fine, of course... when I just simply use Gas Mask to edit the Hosts file, but there are some cases in which I do it by hand. Just a minor annoyance. Love the app, though.