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GitHub User: guy8214
What got me in this was editing my own /etc/host file to have '127.0.0.1' point to my own custom wildcard domain '*.local.me'
After some research, I discovered you can't have a wild card in your /etc/host file. When Ryan says to use 'lvh.me:3000', literally use that rather than editing your /etc/host file. You can then use your subdomains.
Also, since we're on Rails 4 now, check out: