You can think about what seems to be really useful in peoples' everyday lives that will always be making money and creating jobs. Think along the lines of like semiconductors, other materials, integrated circuits, medical imaging, photovoltaics, software, etc. You can see that these are very clearly engineering fields, but there are ways to go about doing some physics in them. For example, if you worked on quantum dot technology, you could be working with quantum computing in graduate school and then perhaps a TV company like Samsung might be interested in you because quantum dots are also an area of research in TV technology. Or if you're doing computationally intensive physics that requires a lot of programming, like astrophysics, quantum chromodynamics, or any kind of grid/n-body simulation you can easily be hired for your programming expertise (and if you look well enough, you can find some jobs that will utilize your mathematical/problem solving abilities from physics and math as well, like working on Wall St. or energy/oil companies).
There's more stuff, you just have to think about it a lot. It won't come to you, you have to think and research it a bit. Of course, no one can tell you what the future markets will look like, but you can be reasonably sure that some things will not go away.
I was just making a joke there.
