If you wish to send a letter in the mail, just not to write the name and address of the sender. At the post office sold the envelopes, letters in which you can send immediately, not sticking brands. You can buy this envelope to put the letter, fill in the fields with the name and address of the recipient and send. You must keep in mind that if you really want the recipient didn't know your name, you need to correctly make the text of the message. The writing style should be formal or neutral, to address the person must, not be too familiar, does not describe any events, information, or any other information that might give you away.
Using the Internet to send anonymous emails much easier. Just remember that, most likely, unsigned message are not serious, and sent to spam.
Today there are many online services that allows you to send anonymous emails. For example, to send anonymous e - letter, you can use e-mail spoofing mail spoofing). This tool uses to send emails SMTP server (Simple Mail Transfer Protocol – a Simple Protocol for sending emails). It can be used to send the electronic letter anonymously, but your IP address will be sent along with him, and experienced Internet user will be able to trace the sender.
In order to send completely anonymous e - letter, it is better to use special websites. They offer to fill out a form to the sender of the letters remained incognito.