Designing a Programming Language

Something that has been really fascinating me as of late is the prospect of desginging a new programming language. I've spent a bit of pet project time at work thinking about a formatting language, and this has opened my eyes to the broader challenge of designing a programming language. What I've found to be a lot of fun is thinking of a concept, or a syntax, and then writing a program with it even though there obviously isn't a compiler to run it afterwards. During university I would wonder from time to time if I were to do a masters, what I would focus on... I'm starting to think that this is an area of computer science where I could make a meaningful contribution.