Portfolio Advice (Programming)

Hey,

I'm graduating this year with a degree in physics, and I've been looking at postgrad degrees focussed on programming (particularly those aimed towards careers in the video game/entertainment industry).

I learned basic matlab and fortran as an undergrad, and I'm currently teaching myself C++ as most courses require good C++ knowledge for entry.

I emailed the university I'm interested in attending and asked for guidance on how much C++ knowledge I should have prior to applying for the course. The response I received essentially said that they occasionally take people with less programming knowledge as long as 'they demonstrate enthusiasm'. I have a lot of extracurriculars so I think I'll make a decent applicant, but he also added that 'a portfolio of interesting work' would help my case.

Hmmm. I'm not sure exactly what I should be submitting. I've been thinking about creating a simple game using C++ (like.. space invaders, or something). I also have an app I made using MIT app inventor, but it's not exactly 'real programming' (it uses building blocks). I guess I could send him a couple of the fortran programs I wrote as an undergrad, but they are.. far from interesting (calculating phonon bands and density of states... hah).

Advice would be greeeat. Are these ideas too boring? Do I need to go back to the drawing board? I have three research projects (two to be published) but they're all obviously physics-related and so I doubt they're relevant enough to be mentioned.