I prefer Hard Business to Hard Tech. Some businesses may be easy on the tech side, but very hard on the customer acquisition side because they require a complete change in the way people think and/or behave.

In that light these businesses were easy tech but hard Businesses that ended up being worth a lot: Ebay, Amazon, Uber, AirBNB, Dropbox, and more.

EDIT

10 of the top 15 Unicorns

Uber - Not Hard Tech

Xiaomi - Kind Of Hard Tech

Didi - Not Hard Tech

AirBNB - Not Hard Tech

Palantir - Hard Tech

Snapchat - Not Hard Tech

Wework - Not Hard Tech

FlipKart - Not Hard Tech

SpaceX - Hard Tech

Pinterest - Not Hard Tech

Dropbox - Not Hard Tech