BlitzMax - With the developing version BlitzMax NG other 'targets' are available: ARM architecture, Raspberry, Android, HTML (Emscripten). RAPID DEVELOPMENT. Just open the IDE, write your code, hit F5 and see immediately the results!
JPEXS Free Flash Decompiler - JPEXS Free Flash Decompiler (FFDec) is an opensource Shockwave Flash (SWF) decompiler.
BlitzPlus - Create 2D Games for Windows.
Flash Decompiler Trillix - SWF Decompiler Trillix allows you to decompile SWF (Flash), convert SWF to FLA, extract SWF elements and edit SWF file. Supports AS 3.0, Flash CS6 & CC and Flex.
Monkey 2 - An easy to use, cross platform, games oriented programming language
SWF Picture Extractor - Free Flash Player for Mac which can be used both as SWF Player and FLV Player for Mac to playback Flash movies with plenty of useful features.