I keep track in much the same way with e books as with p books, I don't. I have never kept p books other than Buddhist texts from the last 4 years. I suppose that is why that thing I wont mention on this thread for fear of derailing this discussion (you know, that thing that starts with a D and ends with an M) has just gone straight over my head.
I suspect I will keep e books longer than p books because storage is so cheap and takes up almost no space. I bet that within 2 years I will accidentally repurchase at least 1 e book I already have
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