I read a story today about a guy who wanted to hide his email IP address. He was purchasing a domain, which was quite expensive (several thousand dollars). The website was related to Greece, the country where he was from, and he discovered that the seller was asking for higher prices from locals. When he had an American friend bid on the same domain, the American received a price 50% less that his. How could the seller know where this man was located? By the IP address of his email. This is just one example of why someone might want to hide their email IP address.

IP address can say a lot about a user, for good or bad. As in the example above, it can be used to see where you're sending email from, and make business decisions based on that. As an online marketer, I'll be the first to admit that some of my business decisions are based on the location of the user. Some are with regards to knowledge of a certain area, ie, I'd be more likely to hire someone from the UK to do work on my sites targeted at UK Internet users. Other are based on previous experience with people from a certain region, for example I've had some terrible freelance writers from India, and now rarely hire people from that country.

Seeing as so much communication is done through email these days, hiding your email IP address and exchanging it for another can seriously increase your business and buying potential. If you're an American living in China, using your Chinese IP address to communicate with others may be inconvenient or even damaging to your reputation. With recent hacks and other malware originating from China, exchanging your Chinese IP for an American one would definitely bring benefits to your business and ease of communication.

There are also numerous other reasons for anonymity while sending email. You'd be surprised what you can, with enough curiosity and tech, find out from the header in an email originating from you computer. You can even find out the admin login name, IP address, and routing information. This is an example of what you might find in an email header.

Received: from ADMIN NAME (xxx(.)xxx(.)xxx(.)xxx) by smtp(.)yourservice(.)com (xxx(.)xxx(.)xxx(.)xxx) with Microsoft SMTP Server id 8.1.311.2; FRI, 16 Sept 2011 12:01:32

Spammers steal IP data every day and abuse it. Do you want to put yourself at risk simply by sending an email address to an unfamiliar and potential harmful recipient?

Other general reason to hide email IP address would include a general desire for privacy and anonymity online, or situations where you fear what the recipient of the email could do if they knew who you were. There are all legitimate reasons, but it's by no means an exhaustive list. Anonymous email services and virtual private networks are two of the ways that anonymous emails can be sent.