The single largest internet advertising venue is unused

Amazingly enough the single largest internet advertising venue is not being utilized! We have adverting on websites and we have email newsletters BUT the most obvious, and I would argue the most effective, venue is not being used: The regular external emails sent from both office and personal email accounts.
Think about it:

There's currently close to 1 billion corporate email accounts in the world and at least as many (if not more) individual email accounts. An April, 2008 USA Today article cites ComScore Media Metrix figures for February, 2008:

Microsoft webmail properties: 256.2 million users
Yahoo: 254.6 million users
Google: 91.6 million users
AOL webmail properties: 48.9 million users

Google has an average of 4 million unique hits per day BUT compared to the number of emails sent it pales (and we all know what Google is worth and why: advertising). IDC predicts that nearly 100 billion emails, over 40 billion of which will be spam messages, will be sent daily worldwide in 2008. This means that over 60 billion email messages are NOT spam and emails between people that know each other.

Google: 4 million hits per day (unique)
email: about 164 million sent every day (SPAM NOT included), even if 75% would be internal emails it would leave 40 million emails daily or 10 times the unique visitors to Google.

Who would advertise in these emails?

Office email: this one is obvious, the Companies/Institutions would advertise for their own business, why not as the employees are sending these emails anyway. The recipients probably knows the sender but that does NOT mean they are aware of everything the sender's employer has to offer. In addition one would make everyone help the sales efforts since they send emails, talk about doubling your sales staff many times over.

Individual email: Just as obvious as these emails could be used to push out 3rd party advertising. Microsoft and Yahoo combined represent over 500 million email accounts, imagine what that could be worth in advertising revenue. Of course motivation is needed for acceptance of the users and that motivation could be as simple as revenue sharing. One could also offer the users to WRAP these emails with their own images with links to various places on the web (facebook, linkedin, eBay come to mind) so the email really become personalized.

One company makes all this possible: WrapMail

WrapMail offers this for both Business at $5 per user per month and for individuals for free. Businesses obviously send from their existing domain email address while individuals get a free email account @wrapmail.com.

The cool thing is that in neither case need anything be installed on anyone's desktop or cell phone.

WrapMail's Business Solution even has full reporting on when recipients click on the wrap and specifically what they clicked on (also available instantly via email or sms).

WrapMail also includes a tool; WrapMaker, where users can make unlimited wraps using their own images and links and for Businesses they include a rule set so wraps can vary based on several factors such as time, rotation, sender etc.

Websites are obvious today, wraps will be come obvious in the very near future. Why not, you're sending the email anyway.