Electroboom - Very interesting and amusing take on electronic and science topics.
Wintergarten - Marble machine MMX is a project I closely follow.
LetsGameItOut - I absolutely love the way he tortures games by doing everything a normal person wouldn't.
Cody's Lab - Another interesting Science/Experiment channel
TerminalMontage - Really funny animations about games!
Slowmo guys - Slowmo nuff said!
vinesauce - Corruption vids are hilarious
Nick Zammeti - Awesome and interesting woodworking channel.
post 10 - Something about a guy going around clearing drains just makes you want to watch for hours.