Suppose, like school buddies Gregg Heubach and Josh Heller, you are young, ambitious, armed with a fresh master's in real-estate finance from NYU and have some serious dough to invest. Where would you start? Messrs. Heubach and Heller have a genius idea. Wait for it…self-serve frozen yogurt.

This spring, the two opened Off the Wall yogurt shops in Chelsea and Union Square, complete with a launch party featuring vodka-root-beer fro-yo. July will bring a new store to Times Square. Next stop: Brooklyn.

...