I am a retired embedded software engineer. My career spanned the big Main Frame computers to embedded ASICs with stops along the way for Mini Computers and much of the Micro Computer products. I also spent a number of years teaching Computer Science in the state college system. Best job for mental satisfaction, worst for pay.
I am addicted to hardware/software that makes things move or react to physical stimuli. Robotics fit this niche quite nicely. My current favorite hardware platform is the Microchip PIC24xxx due to its impressive collection of embedded peripherals. I also delve into FPGAs when the mood strikes.
Other activities include rock collecting and star gazing although I can not remember any of the mineral or star names. Just find it interesting to be with people knowledgeable in their specific field of study. When there is sufficient interest, I teach a Robotics course at the local Adult Education school.
I would estimate that I only finish about 33% of the projects I start. Much higher completion rate when working with others or entering a competition. Much much lower completion rate when I get distracted by an interesting Robotics article. LMR greatly increases my distraction level.