Example nginx config with unicorn and SSL redirection. - I think a lot of it was inspired/copy pasta'd from other gists/examples.

nginx.conf

upstream unicorn {
  # fail_timeout=0 means we always retry an upstream even if it failed
  # to return a good HTTP response (in case the Unicorn master nukes a
  # single worker for timing out).
  # for UNIX domain socket setups:
  server unix:/tmp/unicorn.examplesitehere.sock fail_timeout=0;
}

server { 
    listen 80;
    # domain at http and domain without http
    server_name http://DOMAIN DOMAIN;
    # redirect these to SSL
    return 301 https://DOMAIN$request_uri;
}

server {
    # if you're running multiple servers, instead of "default" you should
    # put your main domain name here
    listen 443 default ssl deferred; 

    # ssl should be disabled through nginx' config, and only used per
    # above listen call
    #ssl on;

    ssl_certificate      PATH-to-PEM (or other file if certified).pem;
    ssl_certificate_key  PATH-to-KEY.key;

    # you could put a list of other domain names this application answers
    server_name DOMAIN

    root PATH-to-APP/current/public;
    access_log PATH-to-APP-access.log;
    rewrite_log on;

    # disable cache on xlsx files
    set $no_cache "";
    if ($request_uri ~* \.xlsx$) {
      set $no_cache "1";
    }

    proxy_no_cache $no_cache;
    proxy_cache_bypass $no_cache;

    location / {
        #all requests are sent to the UNIX socket
        proxy_pass  http://unicorn;
        proxy_redirect     off;

        proxy_set_header   Host             $http_host;
        # proxy_set_header   X-Real-IP        $remote_addr;
        proxy_set_header   X-Forwarded-Proto https;
  proxy_set_header   X-Url-Scheme     $scheme; 
	proxy_set_header   X-Forwarded-For  $proxy_add_x_forwarded_for;
	proxy_max_temp_file_size 0;

	error_page 500 502 503 504 /500.html;
        client_max_body_size       4G;
	keepalive_timeout 10;
        client_body_buffer_size    128k;

        proxy_connect_timeout      90;
        proxy_send_timeout         90;
        proxy_read_timeout         90;

        proxy_buffer_size          128k;
        proxy_buffers              4 256k;
        proxy_busy_buffers_size    256k;
        proxy_temp_file_write_size 256k;
    }

    # if the request is for a static resource, nginx should serve it directly
    # and add a far future expires header to it, making the browser
    # cache the resource and navigate faster over the website
    # this probably needs some work with Rails 3.1's asset pipe_line
    #location ~ ^/(images|javascripts|stylesheets|system|assets)/  {
    #  root PATH-to-APP/current/public;
    #  expires max;
    #  break;
    #}

    #try_files $uri/index.html $uri @unicorn;
    #location @unicorn {
    #  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    #  proxy_set_header Host $http_host;
    #  proxy_redirect off;
    #  proxy_pass http://unicorn;
  #}
}