Right, let me go through my subscriptions to pick a few favorites...
The Right Opinion - drops a multi-hour long video once in a while about a certain person from the internet and goes through their history in detail. Perfect to put on in the background while doing something else, yet very interesting.
CDawgVA - mainly an anime-themed channel, but the guy does lots of funny things, a lot of them related to voice acting since he is one.
Nux Taku - speaking of anime, one of the most chaotic channels I've ever come across. By exploiting his charisma and the inability of people online to distinguish facts from bullshit, he flexes on people, companies, things... anything really. Despite this he is a very reasonable person, open and genuine with his fans and people he interacts with.
Lumpy Touch - a pixelart animator who mostly does Gorefield content. I probably enjoy his streams more than the actual content - it's a jawdropping experience seeing just how quickly he draws. Godlike skill.
Abroad In Japan - what do you get when a brit moves to Japan and makes videos about living in Japan while retaining the sarcastic biritsh humor? Well, this channel.
SomeOrdinaryGamers - an indian tech guy living in Canada. While he does gaming stuff from time to time, his main focus is technology and internet. Very intelligent and levelheaded, yet entertaining and funny.
World War II by TimeGhost - a new episode comes out each week and covers what is happening in the second world war in real time. It is currently 1941 and the Germans had seized Kiev last week.
Lemmino - does short documentaries about pretty much anything. Posts only a couple of videos a year, but they're incredibly high quality.
Internet Historian - covers topics from around the internet in a very comedic way. The editing is insanely witty and funny and his sponsorhip segments are not be skipped because they're equally funny as the rest of his content. How he manages to make videos that are both funny to listen AND look at from beginning to end is beyond me.