As flash games become more intense and complex, The keyboard really has become somewhat obsolete for anything of more the most casual of Flash games.
Thats where Joy2Key comes in.
This nifty little program has been around for Years, and I'm still surprised how little people know about it. Basically you run the program, and Map whatever keys you want to what ever button is on your controller. You can even map the mouse to the analogue stick for menu navigation, and Since flash isn't compatible with controllers (yet), this is really the best option out there. If it wasn't for this Newgrounds"Rumble would be impossible to play with 4 players. Hell this little program can take up to 16 controller inputs if you ever decided to make one big epic multiplayer.
Best of all Its damn Free.
As Flash games keep raising the bar, and becoming closer and closer in quality and complexity to that of console games, it only makes sense, that they be played with controllers.
PS this might help you babies get your last Pink Knight Medals too, lol