There have been some questions about the Sandisk Sansa and using it with e-books. When you play audio tracks on the Sansa and pause in the middle of the song, then shut the unit off, it will restart at the beginning of the song.
However, with e-books from Audible, it will remember where you left off. I sent a question into Sandisk and here's the response I got:
"When playing .AA (audible format) and you hit pause before switching of the player will start at the point you hit the pause button."

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