The Underground Web

Warning: most of the links shown here will only work after you've made some simple changes to your system.

There' a web you can't see and probably never heard about. It's called Hoodwink'd or underground mumbler's club.

_Why, founder of Hoodwink'd, has set up a DNS server able to register non-existent domain names, such as hoodwink.d or anything you like, for free.
Making a few changes on your system, you can become a member at Hoodwink'd and have your own domain at nic.d.

The magic of being a member is that you can leave comments on web sites that only another member will be able to see. How? The comment will be hosted on Hoodwink'd's server, and the web site owner will never get to know it. Freaky? Maybe, but that's cool, isn't it?
Singpolyma's Tech Blog has the instructions to access this hidden web, which I reproduce here (Windows xp only, I didn't test this on any other OS):

1. Open your network connections panel (Start > Connect to > Show all connections).
2. Right-click on the connection you use to get on the Internet (the dial-up connection for dial-up users, and the Wireless Network Connectin or Local Area Connection for broadband, usually) and select 'Properties'.
3. Select Internet Protocol (TCP/IP) from the list box and click the 'Properties' button.
4. Select the 'Use the following DNS server addresses' radio button if not already selected.
5. If there is anything in the first box, move it to the second, otherwise find the automatically assigned DNS address from the status window for the connection and enter that to the second box.
6. Enter 72.36.180.123 into the first box.

Once you're done with that, you're gonna be able to access the links above, but the "regular" web will not be accessible. Undo the changes in order to return to regular web.

More details, way more geeky, you can find here.