[zeta0134]

It certainly starts off that way, but right about the time you have most of your opcodes written and can start stepping through your code, it becomes very exciting very quickly. "Ooh, now I have Tetris getting far enough that I think it's writing to tile memory; can I display that?" "Neat! I wonder if any other games are getting that far. How hard would it be to get the backgrounds working now?"

Suddenly every game you have in your library becomes puzzle box and either works (yay!) or much more often for a young emulator, breaks in a perplexing way. It creates a really rewarding feedback loop, where tiny changes to timers and status registers can have big sweeping effects on your tests. And all your tests are themselves games, and usually fun to explore anyway.