I'd dearly love one that does color but I don't think that can work with e-ink, or at least that's my impression? Which makes me sad cause it'd rock to have all my field guides and stuff on a kindle too.
I think there are e-ink technologies that use color, but I haven't researched it for a while.
I love our Kindle! It is a pleasure to read on (though research suggests I read more slowly on it than in a real book, but I haven't noticed). If you're reading novels or poetry or things along those lines, I highly recommend it. My wife and I have one, and I just know that someday we're going to need to get a second one. Not only do you get free classics, but there are often other books for free available as well (especially, for example, the first book of a series).
Two things that are harder to do on a Kindle though: 1.) flipping back and forth, and 2.) looking up footnotes (works fine, but is kinda slow and clumsy).
You don't need a Kindle to download the software though. Not as much fun to read on a computer, though reading on a phone is ok (not great, but certainly do-able).
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