Safari - Displaying every website I want, except one???

I am trying to visit a website on my machine which simply does not work. All I get is a message saying the following:

"Safari can’t connect to the server.
Safari can’t open the page “http://www.domain.com/” because Safari can’t connect to the server “www.domain.com”."

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I can visit the website on my Blackberry, I can visit it on my computer at work, but it simply refuses to load on my home machine.

I have tried emptying the Safari Cache, flushing the DNS in Terminal, restarting my computer numerous times, but still absolutely nothing. It has been over a day now.

Is there anything else I could try?

Your OS X version is _____.
Safari version is ______.

OSX: 10.6.6
Safari: Version 5.0.3 (6533.19.4)

Ok, you're up to date. Do you have another browser on your home computer? Try a different one.

What browser is loading it at work?

Yep, tried Firefox and does exactly the same.

Safari is the one loading at work - same OS, same Browser. It is just completely bizarre !

Compare your settings in Safari > Preferences at home and at work, especially Security

Clicking on your link shows the page not found message, and redirects to the web site. Using anything to prevent redirect or Advanced Preferences preventing this?