CloudPaste is a modification for jailbroken devices that lets you share clipboard contents using icloud, you can eg copy text directly on your iPhone and go to your iPhone, press paste and you're pasting the text you copied into the IPAD or iPod Touch.

Of course you need to have the modification installed on both devices. There is also a version for Mac

Do not add icon or Settings.

Requires iOS 5.

You can download for $ 2.49 in Cydia.

The'll find BigBoss repo.

You need to have done the jailbreak.