Example of a top-level domain that is a hostname

On Wikipedia I read that TLDs can also be hostnames:

However, other top-level domains, particularly country code top-level domains, may indeed have an IP address, and if so, they are also hostnames.

As I understand, this would be a domain like http://org/. When I enter URLs like this, I usually get transferred to something like http://www.org.com/ . Is there any live example of a web site like this?

Solution

http://dk/ is such an example:

LANG=C wget -S http://dk/
--2018-02-27 23:44:23--  http://dk/
Resolving dk (dk)... 193.163.102.58, 2a01:630:0:40::58
Connecting to dk (dk)|193.163.102.58|:80... connected.
HTTP request sent, awaiting response... 
  HTTP/1.1 301 Moved Permanently
  Server: nginx
  Date: Wed, 28 Feb 2018 04:44:24 GMT
  Content-Type: text/html
  Content-Length: 178
  Connection: keep-alive
  Location: https://www.dk-hostmaster.dk/

What you observe in your browser is your browser empirical rules to tackle .COM automatically if the first direct DNS query fails.

If you want to educate yourself, have a look at https://www.icann.org/en/system/files/files/sac-053-en.pdf :

SSAC calls a domain name that consists of a single label a “dotless domain.” Applicants for new gTLDs who ask the question posed above want to know whether or not a dotless domain would be handled by Internet infrastructure and applications in the same way as other domain names. In this report, the SSAC finds that dotless domains would not always work as expected given current DNS implementation and existing application behavior. In particular, the SSAC finds that the way in which domain names are interpreted in different contexts would lead to unpredictable and unexpected dotless domain behavior.

This also explains why you will not find this "feature" in gTLDs (old or new ones): it is explicitely prohibited by ICANN (for no very good technical reasons, but mostly after the SiteFinder fiasco). So you will need to look in ccTLDs.