FlashDevelop is a donationware IDE for Adobe's now-open source Flex framework--basically Flash for programmers instead of animators. Between the two, you can make Flash-based software for free now, which is kind of a big deal. Maybe everyone already knew this, but I was surprised by it. Pleased, granted, but still surprised.
At this point Flash seems to have achieved what Java wanted to be: a slick, machine-portable, Internet-aware programming language with an unbelievable level of market penetration. It also has the advantage of a runtime that's very small compared to a JRE. Java has managed to achieve a valid niche as a server-side technology, but it's not much of a force on the consumer side any more.
But the weakness of Flash has been cost for the development tools, as far as I have been concerned, and I'm sure lots of other people feel the same way. You can develop Java for free, and you don't have to use a command line any more. You can get a limited copy of Visual Studio (pick your variant) for the price of a download. But Flash is what, $600 nowadays? Even Flex Builder is at least a couple hundred bucks. Moreover, Flash (the app, not the API) is truly terrible for programming, what with that weird floating psuedo-window and its continued dependence on the timeline.
Which leads me inescapably, knowing people as I do, to the conclusion that a great deal of Flash's popularity has been built on pirated copies of the software. So it was probably only a matter of time before Adobe decided to open the software up with a free/cheap version, simply reserving some of the goodies (bonus UI components, for example) for paying customers. Which is, as far as I can tell, exactly what they've done.
Anyway, the politics of it aside, you can make Flash for free now. This is a very good thing. I'm guessing they'll screw it up any day now.