Begged for by Apple fans for so long (even though it's a barely used function for a large percentage of users) it's finally turned up in the iPhone 3GS. The implementation is superb, with a round magnifying pane appearing if you hold your finger over some text.
The iPhone 3GS will then attempt to smart-recognise which text you're after, and auto select it for you. Should you need more, you can drag the copying field using little markers at the corners.
And it doesn't just stop there, you can drag and select swathes of text and pictures together, ready to pasted into a document or other application, as the phone will remember what you've placed on the clipboard even if you shut down the program.
This means that should you see a cool image on a website, you can simply hold your finger on it, select 'Copy' from the pop up menu, and paste it into a text in order to send it to a friend as either an MMS or move things up a technological notch and send it as an email.
Again, one of the things with the iPhone is that it doesn't necessarily bring something new, but what it does do it manages with mouth-watering simplicity (in most cases - things like message searching obviously don't manage that 'cool factor' at all).
It's a great system, one that you might not use all the time but will certainly miss should you use it on the odd occasion and then have to perform the same function on another non-Apple phone.
It's intended for basically calling people in your phonebook and helping you interact with music. However, there are a couple of faults: it rarely manages to work out what you're after when using the bundled buds, and using your own headphones means the repeated voice command comes out the speaker, so if you're listening to Aqua, the train carriage will know about it.
However, when it gets it right, and you ask which track is currently on or you want to start playing a new album simply by saying its name, it is really cool, so hopefully Apple will update this in the near future to be more accurate.