I treat all E-books purchased with DRM as rentals. When making a decision whether to buy or not, I look at the price and consider whether I'm willing to pay this much to rent the book for an indeterminate amount of time, possibly as little as 3 months. Quite often it turns out that the price is too high. But I never delude myself that I actually "own" any of the DRM-restricted content that I paid for.
> I treat all E-books purchased with DRM as rentals. Good for you. Nobody else outside of HN does.
Fine let's say it's not a rental, and forget about the DRM issue for a second.
But what's your cost in keeping the data "alive"? I could copy it from machine to machine, maybe backup it on S3 (or similars), but all that has a cost (time, money, new reading devices, etc).
A physical book has a cost as well: space, weight, etc.
At some point, abandoning the book may be more cost effective, and even if digital books have a 'expire date' it looks like they may be cheaper in the long term