I know I'm crazy behind on this, but as XKCD reminds us, there are always going to be plenty of people who haven't heard about something "everyone knows."
In that spirit, who knew about all these free online college courses?! From really great schools?! My friend, Lianna introduced me to Coursera the other night. I immediately signed up to take Health Policy and the Affordable Care Act, Modern & Contemporary American Poetry, and Introduction to Finance. I wish I knew enough (read: any) calculus to take Game Theory. I wish I had time to take all the classes. Because there are SO MANY. A quick Google search turned up open course programs at Yale, Berkeley, MIT, Carnagie Mellon, UMass, and lots of others around the world.
I think these are pretty amazing resources, especially when you consider how expensive education continues to become. None of these courses, as far as I can tell, offers any kind of certificate or degree but the chance for free enrichment is a pretty wonderful one. I might even take some French again and cross #15 off the list.