Fry's has a sale on Z22 Palm Pilots right now for $59.99. That's a pretty low price to start paperless caching with. It's not extremely advanced, but if caching is all you'll use it for, it's a good deal.

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I just bought one of these for myself, and this thing works GREAT with Cachemate! I've got tons of memory to spare, and I've got several eBooks on it, too. It's bright and in color, and going to work perfectly. I can answer any questions about it's abilities if anybody has any.

So I thought I would check Fry's out to see if they had any on the shelf. Nope. but they did have some older B/W palm m105's for $34 and the Z21's for $45. So depending on your budget there is all kinds of stuff out there...At Fry's that is.