anti copy protection for distribution

Hello developers,

I have created a game for the windows7 platform and want to put it on the internet for a small fee. I was wondering if anyone knows a good copy protection mechanism which i can use. Until now I found one product that seem to fit my needs, the wrapper from exesecure. Has anyone got experience with this copy mechanism system (or another one)?
Please let me know. And I know that each game will be cracked eventually but I go for the 20/80, so for now I just need something.

Cracked it will be when its popular enough to spend the time
doing it.

If you have a "small" game, even a simple protection (keeping it from simply sending it to someone else) should suffice.

Think about a shareware model here, only locking the
full features.
You want the game to circle as much as possible to get potential customers to notice it.


How about the simple way: receive the payment from a customer with a real name, and sending back a specifically generated unlock-key.
This keeps many people from spreading their (retracable) serial key to not get into trouble.
Would be even more fearful when the entering the unlock key displays part of their name at gamestart
So you could encode like their initials into the unlock-key.

When you look for a payment processing service:
as far as I understand you can upload a list of pregenerated unlock-keys to bmt micro, wich sends it to the cutomer.

http://bmtmicro.com/developer-what-we-offer.html

(again with the simple logic, that the user paying knows that the key can be linked to him)