> When I left the company they let me buy my books for $5, so I took them with me, and took them to my next two jobs. I stopped carrying them when everything the contained could be found online.

Not just online but also more up to date.

This is a drawback of books, they don't auto-update and upgrades are quite expensive. In IT I don't see a point to keeping them archived anymore.

I still use them for learning new topics though.