The Wikipedia feature is major cool. You can select an article or multiple, then download them all as a PDF. You can also send said collection to a Wikimedia print site and get it hard-copy and bound for what I think is a quite reasonable rate.

The selection can be re-ordered, divided in to chapters, and you can create a cover for the whole mess.

I liked the serendipity of looking stuff up in an encyclopedia, I suppose a lot could be what you grew up with. I was quite amused by the fact that my parent's encyclopedia pre-dated the end of the Vietnam War! Made for some interesting reading. And that is the big weakness of the printed encyclopedia, you have to buy the yearbooks and put the little stickers in your originals to cross-ref them. Not viable long-term.