I have had some books stored up since forever, and graycat's post did motivate me to finally get around to reading them, but I find it hard to integrate into my daily routine. His 24h challenge killed my productivity for a day, and I can't really afford to get distracted by some tricky proof when I'm supposed to do something else.
In a different comment chain on the same submission (https://news.ycombinator.com/item?id=15024640), he challenged the commenters disagreeing with him to do these exercises in 24 hours. The tone was pretty abrasive, TBH, but I found the questions interesting enough that I tackled them in earnest.
I posted my solution attempts, so don't scroll down too far if you want to try them on your own ;)