I tend to romanticize the Game Boy Advance somewhat because it was the last pure game system from a major manufacturer. It has no operating system or user-editable BIOS. If no cartridge is inserted, it doesn't even play the full splash screen. It boots directly into the game immediately when the system is turned on, and it gives full trust to whatever program it reads.
It's also pretty simple. It has 10 bits of input, with no touch or motion controls. It is usually programmed in C, unlike earlier consoles which were often programmed in platform-specific assembly. And, again, it has no OS to contend with.
For these reasons, the Game Boy Advance interests me as a programmer. I want to do some kind of project with low-level systems code targeted at a specific device, and I want to do some game programming in C. Doing these at the same time would be awesome, so my goal for the next several months is to learn enough to make a decent-sized program that will run on a GBA and then run it on a GBA.
I was almost done with RNG, Part 2 when my PC crashed today. I don't really have the motivation to rewrite it now, and I might be very busy tomorrow, so I will probably rewrite it on Thursday.