I knew I was leaving something out of the Zune post. Another scam by Microsoft: their currency system. When you buy music from the Zune online store, you don’t use cash, or even credit–you use Microsoft “points,” like Disney Dollars or funny money.

How is it a scam? Well, first off, the points are not made equal to dollars or cents, there’s an ‘exchange rate’ at play here. Microsoft never actually quotes real money amounts when stating the price of a song, they say it costs 79 “points” instead. That makes it sound like Microsoft is selling music for 79 cents, but because a $5 purchase of “points” gets only 400 points in your account, that 79-point purchase really cost you 99 cents–the same as the iTunes Store.

Of course, there are benefits to having the point system. Unfortunately, those benefits are for Microsoft, not for you. For you, it’s nothing but a liability. In addition to fooling you with an exchange rate, Microsoft also does not allow you to buy exactly the number of points needed to buy music–you always must buy too many points. When you buy from the iTunes Store, your credit card is billed for the exact amount, 99 cents. But in the Zune Marketplace, you can only buy points in whole-dollar chunks, starting at $5. Since music costs 99 cents a song, you have 5 cents left over when you use up the purchase amount. Essentially, when you buy a song for 99 cents, Microsoft is not giving you your penny change. Or, at least, they’re keeping it in their pocket until you buy 100 songs.

Now, to you, this may be small change. But imagine millions of customers buying less than 100 songs. Say, 10 million people buying ten songs each is an extra million bucks Microsoft squeezes out of the deal. Though you might think that a company worth umpteen billions of dollars wouldn’t need to create a scam just to squeeze another million out of gullible customers.

But the scam doesn’t end there: you can only buy Microsoft points in denominations of $5 or higher. Which means that you can never buy one song. You have to buy in chunks of five. Which, of course, most people will not do. Most people will either never use up all the points they have, or they will take time to do it, which means more millions of non-reimbursed dollars for Microsoft, and more time for the pre-paid cash to generate interest for Microsoft before they have to pass the money on to the music labels.

Of course, unless you read a review like this, you don’t learn about it until you’ve plunked down $250 for a Zune player, by which time you’re committed. And then you discover that Microsoft has no respect for you and believes you’re just another sucker who’ll do whatever they want.