This plugin looked like it could do the job, it allows you to create a VERY simple product which generates a coupon code. However, I was disappointed to discover that any nice features aren’t present in the free version. I understand that this is a necessity if you are selling premium versions but I would have appreciated a few more options. The free offering isn’t worth the download IMO.

However, It did work without any fuss, so I’ve generously given TWO additional stars as a reward for the devs achievements on that front.