How I managed to get the words 'insanity' and 'genius' as sub categories there in the top left still baffles me though.
Computers are weird things, and programs (well, more generally, algorithms) are even weirder things sometimes.
In this case I am betting something triggered it to present the other words in the title of this post to you as sub-categories.
I got different categories... "green" and "thing."
Try clicking some of those sub-categories! More show up that weren't there before, and you can go on a little adventure :)
Yeah those sub-categories change nearly every time.
I do enjoy a good google adventure though. Many of the top hits on any subject nowadays aren't usually the best. Maybe the publisher was the best at using tricks to get their work there, but that's about it. Searching random thoughts and word combinations on youtube, then sorting the results by newest first; that's a fun little game as well.