Ask HN: How do I learn Excel as a programmer?

I've come to appreciate some facets of Excel and feel it could be a valuable tool in my arsenal in addition to other languages I know. There seems to be a dearth of material on learning Excel targeting programmers/SW devs, does anyone have any good resources to share?

I'm looking for things along the lines of Joel Spolsky's "You Suck at Excel" https://www.youtube.com/watch?v=0nbkaYsR94