That is basically the key point to every get paid to read email site.
Get paid to sites came about back in February of 1999 and all started with its forefather, a site entitled Alladvantage.com. The objective with Alladvantage.com was to download their version of an advertisement bar that flashed you ads of different sponsoring companies that would pay you a certain fixed or variable perecentage of their revenues. This is known as a get paid to surf company. A lot of failed and most are hanging from a thread.
The get paid world broke off into several tangents :
get paid to play
get paid to surf
get paid to write
get paid to etc, etc.
Get paid to read email I believe (and I can say that because I am a sucker to all of the gimmicks) was Sendmoreinfo.com. The first get paid to read email was born and all were happy!
This is the idea. The company gets advertisers to pay them and a portion of that money is paid out to members based on certain criteria.
Most sites work the same way whereas a few have different pay scales. Take for example Sendmoreinfo.com; 5 cents for every email that you read and 2 cents for every email that the people that you and only you sign up. Payment levels are usually around $20-$50. You think that they would send you like 50 emails a day, but that wasnt the case and never would be the case.
So if you get 10 emails in a month (this is fictional data and not actual and doesnt even come CLOSE to being actual data) and sign up one person and they get 10 emails, you make a whopping $0.70. Sound rough? It is rough.
The downside to any paid email program is that they expect you to get like 30 people to sign up and youll barely barely barely make the minimum payment. This sometimes only occurs if your referrals are clicking on every email.
Other companies have offered $30 payment levels, $0.03 per email and refferals up to 4 levels. One program that I did like was themail.com that had a 10 level referral line and was a real email account company. You would get 1 cent for every 4 emails you read or sent out to anyone and the same for referrals (percentages vary for lower levels of referals)
Overall, most companies do pay and I must say that there is a potential to make lots and lots of money, but only with a LOT of referrals and I mean over 1000 to get maybe $150 or so. I still suggest get paid to review and get paid to surf sites.