There is no shortage of programming languages, from the well-known ones (Java and C++) to the outright esoteric (intended just for research or even humor). While the vast majority of people learn to program the most-popular ones, the lesser-known programming languages can also secure you a good gig in a specific industry. Which languages? Client-server programming with Opa, Salesforce's APEX language, Mathematica and MATLAB, ASN.1, and even MIT's App Inventor 2 all belong on that list, according to developer Jeff Cogswell. On the other hand, none of these languages really have broad adoption; ASN.1 and SMI, for example, are primarily used in telecommunications and network management. So is it really worth taking the time to learn a new, little-used language for anything other than the thrills?