Frash enables Flash on jailbroken iPhone
Removes even the toughest stains

Frash, the app that allowed jailbroken iPads to access and run Flash through Safari, has been successfully ported to the iPhone and iPhone 4, finally allowing access to hundreds of thousands of websites that use Adobe's standard. (Update: not video sites)
Development on the iPhone version has reportedly been aided by well-regarded iPhone jailbreaker Comex, who was also behind the recent ‘slide to jailbreak’ website.
The app runs on iOS 3.2 and above, and is compatible with every Apple device from the iPhone 3GS/iPod touch 3G and above.
It needs to be jailbroken first, though, as you really should expect by now seeing how it goes against everything Apple stands for (HTML5).
Remember, jailbreaking may not be considered illegal in the US, but it does void warranties and can, in some unfortunate situations, break your phone. So if you do decide to go down the path of the jailbreaker and fall into a big bricked pit, don’t say we didn’t warn you.
IntoMobile