flash memory mp3 players where you can top up memory using memory cards, like Rio Cali. I agree that there are not too many but they are there.
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Then I could decide if I want a 256, 512, 1GB, etc. Compact flash is cheap enough now I could have several 256MB cards around to swap in at will. Sure a hard drive would be cheaper overall, but I would rather have a solid state device for the durability.

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