Linus! Congrats on your 1million subscibers!
I will make a top 3 of my favourite series:
1 - The WAN Show - As a geek and a 15yr old spanish, I hear the news in the techy world and learn english! Thanks to Youtube and english content I have a fluent English without studying it!
2- Techquickie - I like a lot techquickie, is a fast way to learn things and to explain some terms you have explained to my friends, like when a friend didn't know what AA was and I sent him te video.
3- Build Guides - I mounted my PC using one of your build guides, ands its a useful buyer guide too!