Confidentiality Statement in emails

[DomainMagnate]

Many people/companies add a Confidentiality Statement at the end of their emails.
Are there any legal reasons, like restricting liability? Or is it just added to make it look more legit

Above all I'd like to know what are the legal applications of this and how is this different when such an email is sent by a company, or an individual?

Here are some examples I've seen:

Confidentiality Warning: This e-mail contains information intended only for the use of the individual or entity named above. If the reader of this e-mail is not the intended recipient or the employee or agent responsible for delivering it to the intended recipient, any dissemination, publication or copying of this e-mail is strictly prohibited. The sender does not accept any responsibility for any loss, disruption or damage to your data or computer system that may occur while using data contained in, or transmitted with, this e-mail. If you have received this e-mail in error, please immediately notify us by return e-mail. Thank you.-

LEGAL CONFIDENTIAL: The information in this e-mail and in any attachment may contain information which is legally privileged. It is intended only for the attention and use of the named recipient. If you are not the intended recipient, you are not authorized to retain, disclose, copy or distribute the message and/or any of its attachments. If you received this e-mail in error, please notify me and delete this message. Thank-you.

*************************************
The information transmitted herewith is sensitive or business confidential information intended only for use to the individual or entity to which it is addressed, and may be legally privileged . If the reader of this message is not the intended recipient, you are hereby notified that any review, retransmission, dissemination, distribution, copying or other use of, or taking of any action in reliance upon, this information is strictly prohibited. If you have received this communication in error, please contact the sender and delete the material from your computer.

The sender believes that this e-mail and any attachments were free of any virus, worm, Trojan horse, and/or malicious code when sent. By reading the message and opening any attachments, the recipient accepts full responsibility for taking protective and remedial action about viruses and other defects. The sender's business entity is not liable for any loss or damage arising in any way from this message or its attachments.
**************************************

and my favorite

I WILL KILL YOU IF YOU STEAL ANY OF THIS INFORMATION. HAVE A NICE DAY.

thanks

~MG

[BILLBO]

These 'statements' have no contractural legitimacy in law (England & Wales at least, but I would be surprised if in any other western legal jurisdiction as well).

They are simply added to emails in the hope that the recipient will not publish the contents publicly. However the recipient has not agreed to such and therefore no contract exists. Perhaps they are trying to use the 'statements' to imply the same legal basis as the statement 'Without Prejudice' (this means that the contents may not be relied on in a court of law). This attempt would be, IMHO, thrown out by any court in England.