Give people an incentive to spend more with you
If you are ever considering the pricing structure for a product or service then pay special attention to how your prices increase.
I've just been browsing the Feng GUI website and after deciding I would like to take this relationship further, I wanted to find how much it would cost me to use. The site displays a clear price grid, which conveys various price options. However, as the price increases I don't seem to get any more for my money (except for a longer validity date, which isn't going to persuade me to act fast). It's commonplace to expect to get more value for money when you make bigger orders, known in economics as Economies of Scale. In the Feng GUI example, I have no reason to purchase any more than 10 credits at a time, unless I specifically need to use more than 10 right away. If they re-thought their pricing they could persuade me to buy more credits by offering some for free as my order increases. For example, if $25 gets me 10 credits, $50 should get me 25 credits and $100 should buy me 100 credits etc. Have you seen any good examples of this pricing structure being used?