it's called InstaPaper and it lets you put a button on your web browser so that when you come across an article or something you want to read but don't have time you can just click the button and it get's added to your own personal newspaper (website) that you can go and read at a later time.

The iPhone has apps for it too, so if you come across an article on your phone but don't want to read it all on a small screen you can click the instapaper icon and then read it on your home or work computer later.

I'm sure other phones have apps for it too.

Pretty darn cool I must say.