for example.

you have refferal html link for amazon.com.
lets say your brother (or you) click on the link on your homepage and you will be redirected to amazon.

than you buy an ipod.

1.)
amazon gives in several countries a 5-10% cashback on several products.
if you buy an ipod for 200usd you get 1 -2 month later an electronic voucher with an code over 20USD.

2.)
your brother (you) gets refferal cashback from amazon 2%- 7%

3.) you earn miles through the payment with your creditcards.

4.) in some countries like japan, you get a double dip with the creditcard .
for example Lufthansa UFJ creditcard gives you 1mile per 1usd, but you get in the own UFJ points program a double dip point for 10usd you get 1 smile point.

so if you know how to do it, you can double, triple , quadruple dip with the right cards and the right tactics.

about amazon, this is just an example, you can use these cashback sites which are mentioned on FT to get a cashback.

about dipping, as miles are similar to cash for me, if i get a cashback , its the same as getting miles for me.

dp