I think there's still tremendous value in a university education, but no longer think you can get the value of that education by default -- you'd have to know how best to benefit from it, and if you have to do a bunch of work in order to get value, you can do a bunch of work and save yourself $100k or whatever. So:
  • Find an existing business and buy it (there's a website where small business owners are selling their businesses). What you learn from running it (and probably running it into the ground, failing, as per @k00b's recent post) will be priceless and you'll never forget it.
  • Learn to code and make a bunch of projects that do shit that you care about. It doesn't even matter what it is so long as it's a thing you care about and want to exist. Work in public, on github.
  • Write a blog summarizing the stuff you're learning as you make these projects. Work hard on writing clearly and getting better at writing. Have somebody you trust, and who you think is a good writer, give comments on how you can be better.
  • Pick some of the classics, fiction and non-fiction. Read them. Think about them. See what other people have said about them over time. Blog about this stuff, too.
Basically, anything that has you a) building stuff, and b) writing, will put you ahead of most of the people who stumble through university doing all the default things; and will cost you essentially zero, unless you do something special, like buying a business.