I am System and Embedded Programmer. I am always curious to know what make wheels roll.
I have worked on Boot-loader Programming, Device Driver Programming, Kernel Programming, File-system Programming for my own 32bit x86 OS started from the scratch.
I also use to do Embedded programming but till now its just functions based while i prefer to know core stuff since i am a developer not the end-user.
Keep moving forward. Do work of your interest then work doesn't remain work, it become enjoy.