When Apple decided to make the Siri voice command Assistant exclusive to the iPhone 4S, hackers worldwide took it as a challenge.
Since then a few successful ports have managed to prove that Siri doesn't need a dual core processor to work, though the quality of the microphone on older handsets does spoil the experience somewhat.
Apple enthusiasts managed to port Siri on the iPhone 4 and even iPhone 3GS by getting access to iPhone 4S system files and then installing them on the older iPhone version.
However, these attempts were illegal and in violation of Apple policies due to system file migration. But now, iPhoneHelp reports that a new tweak enables iPhone and iPod Touch users to port Siri without needing system files from Apple's latest iPhone.
Siri0us purportedly enables the digital assistant to take dictation without infringing on Apple's policies. Developer Eric Day explains his tweak as "Siri dictation for your iOS 5 devices. No iPhone 4S keys/files required."
Unfortunately Siri0us does not at present offer the functionality to set alarms, check weather forecasts, set reminders, or check for nearby businesses etc; but the writer says the dictation feature is very much comparable with the actual Siri.
The app doesn't work for the iPad at present, but if you want to try Siri dictation on your iPhone or iPod Touch, you can add this repo for the tweak to download Siri0us.