I've seen a ton of "how-to" videos on the web showing how to use a specific piece of equipment or how to do a specific technique. These are all fine, and might teach me a thing or two, but very few address knowledge over equipment.
One of the most lasting inspirations I've seen is the Field of View series by Chuck Peters and Digital Juice. Field of View takes a different approach, addressing techniques from a philosophical perspective by first asking "why?"
My favorite episode is "The Warehouse," which addresses production quality and control of the shooting situation, punctuated by illustrating the point right in front of your eyes.
Field Of View is almost mandatory viewing for anyone looking to expand their skills, not their budget.