lucid dreaming
Visualizing/Imagining/Creativity (there was an article about someone training like Tesla, can't remember his name)
sensory - increasing the power of senses (a few years ago, I remember going for a walk blindfolded, in a camp I had gone to)
etc. How did you do it?
I was wrong, smart-content is not by itself pointless entertainment. It's all about your state of mind while reading it. I believed that reading smart-content would make me smarter. Like you, I've read hundreds of hacker news submissions. Yet I gained nearly no knowledge.
To answer your question; you've already figured out what you should and shouldn't read. What -really- matters is -how- you read. Don't skim and expect to become smarter automatically. Because when you do this, you assume the author is right all the time. You need to be critical.
And ooooh, I've heard that one so many times "just be critical". I've never understood what this meant, until I decided I wanted to truly understand my texts. It can take me over five minutes to read a single page since I've started trying to truly undertand a book.
Try some of these, see which ones you like and which ones you dislike. Find the ones that work for you. I've tried these and found that they help me dig really deep into any text.
- Doodle and write in books. Honestly - Collect and present a text's statements and opinions as fact. I can assure you you will find logical inconsistencies - Summarize texts - Force yourself to capture the essence of a text within one sentence