Are there any truly useful books on the subject of concentration and how to improve your focus?
Meditate.
Gorilla Mindset
>>9133436
Is meditation really beneficial? I've heard mixed things about its usefulness. I've tried it myself, though possibly not for very long, and it didn't seem to provide much improvement.
>>9133431
have you considered applying to concentration camp?
>>9133698
Teehee xD