Our project routing is base on subdomain.

a.example.com go to page A;
b.example.com go to page B.

So that in development, we can't use "localhost" or "127.0.0.1" to test our site.

At office, I was setting up a DNS server to resolve "*.leonardo" to my computer LAN IP for that. Colleague can access my computer using that domain to preview our website.

However, I just got my MacBook Pro, I would like to develop anywhere now. But I don't want to change OS host file for this... I remember there are some domain name that always resolve to IP 127.0.0.1 for development. Google and found http://readme.localtest.me/