I've been working on a cool little windowSWF widget for the Flash IDE that allows you to easily preview custom styles for the built-in UI components without having to compile your project each and every time.

windowSWF preview component

I'll be showing the code for this in my session on JSFL at Flashtival, Rotterdam this coming Monday after which I'll make it available for download -- if you're heading out to that conference you can consider this a sneak-peek of more exciting stuff to come ;)