Love the answers people are posting!
I, too, have learned MANY things that have saved me a ton of money. Fixed my dryer problem. Learned how to take apart my dishwasher drawer. Saved $100, believe it or not, by watching a video on how to replace the burned out bulb in my Honda Odyssey clock (which requires you to remove the entire dashboard, but is a $2 part from Radio Shack). Was quoted $800 to fix my minivan automatic door so it would shut properly--tried youtube and got it to work. Admittedly, it's not like it used to be, but at least it opens and closes.
New recipes, knitting stitches, braid styles, how to make a pill-box hat, etc etc are all things I've learned on youtube.