I bought and used this software back in version 3.1, but stopped using it when I had trouble keeping a dedicated midi keyboard/computer setup in place. I was looking for something like I used to learn touch typing, and Music Space Invaders fits the bill. Get the demo and try it out.

The current version has some notable improvements over the 3.0 version that I find make it quite attractive again. The software has many sound queues that enhance the learning process. You can now completely adjust these to your liking. You can also choose the direction the notes come from depending on your current learning focus.

Other great features that remain unchanged from the previous version are a fully functional downloadable demo version, native modern macosx implementation, and excellent midi integration. I haven't used the Grade Book or Lessons features much yet, but they seem like an obvious must for any sort of learning software.

I couldn't find the current price for the software, but I paid $50 for it in 2004 and in retrospect have no complaints.