I wrote a plugin just like this, and every day, I have it present me with a quiz based on a summaries of the first paragraph of the pages I read over the day.
Basically, I was reading way too much Wikipedia and not actually storing much information, so I have the extension shame me if I don't remember what I read.
We absorb the words in front of our eyes even if we're not conscious of it. A topic that you glossed over may come up in another context and remind you of that wiki article.
It shapes who we are.
And sometimes knowledge of the existence of a topic is valuable.
Basically, I was reading way too much Wikipedia and not actually storing much information, so I have the extension shame me if I don't remember what I read.