First of all - the brushes are amazing - thank you!
Secondly - it's a great class. Once you get used to how things work you can create versatile, abstract backgrounds in no time.
Seen above is my first attempt. I'm quite fond of it, however I did lose some control of what I'm doing in the bottom bit - it looks a little too edgy and not as flow-y as I intended :) but it's definitely more than I expected to find myself making on the iPad any time soon.