With Quetim there's no need to type SMS on your mobile phone any more. This means no more hassle with multi-tap or the cursed(!) T9 text input.

What you need:
Any java-enabled camera phone and a computer with internet.

How it works:
Install the quetim java application on your phone.
Type the SMS from your comfortable seat behind your computer at http://www.quetim.com.
Scan the barcode the website generates for you with your phone. The application uses your phone's camera to do this.
And voilà, the text appears in an SMS on your phone!

Check the links above for the full info.