The raw HTTP requests can be spoofed for even greater flexibility.

$telnet www.php.net 80
Trying 64.246.30.37...
Connected to rs1.php.net.
Escape character is '^]'.
GET / HTTP/1.1
Host: www.php.net

HTTP/1.1 200 OK
Date: Wed, 21 May 2004 12:34:56 GMT
Server: Apache/1.3.26 (Unix) mod_gzip/1.3.26.1a PHP/4.3.3-dev
X-Powered-By: PHP/4.3.3-dev
Last-Modified: Wed, 21 May 2004 12:34:56 GMT
Content-language: en
Set-Cookie: COUNTRY=USA%2C12.34.56.78; expires=Wed,28-May-04 12:34:56 GMT; path=/; domain=.php.net
Connection: close
Transfer-Encoding: chunked
Content-Type: text/html;charset=ISO-8859-1

2083
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01Transitional//EN">
...