With iPod 1.1 software or later you can scroll backwards or forwards to any point in a song while it is playing. This feature is sometimes called "scrubbing."
This feature is useful if you want to go to a particular part of a song or recording, such as an audiobook.
Tip: You can also press and hold the Fast-forward or Rewind buttons instead of scrolling to go to any point in the song.
Note: Scrubbing is only available from the Now Playing screen. It is not available via a workout from the Nike+iPod menu.
If you have an iPod shuffle, you can use Fast-forward and Rewind, but you can also find additional audio book navigation tips here.