
The Flash port project is called Frash. Recently it became available for iPad, now iPhone users can install it on their devices. Of course you need to jailbreak, since Apple doesn’t support Flash in iDevices.
Credits go to hackers for the Frash port and for compilation.
Here is the video proof from redmondpie:

MuscleNerd, famous hacker from DevTeam, has announced via Twitter that an upcoming comex release will jailbreak all 4.0 devices. This will include latest iPhone 3GS, , new iPod Touch and iPad.
jailbreak for all devices at 4.0 is already handled by upcoming @comex release 🙂 so, good time for iphone4 unlock stuff
Comex is also well-known, he authored the 3.1.2 and 3.1.3 jailbreak called Spirit. He’s also recently demonstrated Frash, an upcoming release of Flash for the iPhone and iPad.