What is my IP? The nginx way...

Pure nginx solution ;)

curl -sf ip.socha.it

or

curl -sf ip.socha.it/eol

Nginx configuration:

server {
        listen 80;
        server_name ip.socha.it;
        default_type "text/plain";
        location /eol {
          return 200 "$remote_addr\n";
        }
        location / {
          return 200 $remote_addr;
        }
}