At one stage, developing Flash games required an expensive licence, or piracy. Thankfully, the open source FlashDevelop, along with things like the Flex SDK from Adobe, has changed all that. I've been working on a project with TuDocs Studios which has benefited from the availability of FlashDevelop, but admittedly I hadn't got my teeth into much coding. I decided I needed to learn ActionScript though (it's been on my 'todo' list for years!), and it's been more straightforward than I had expected.