Seeing as today's machines have insane computing power and near endless memory, it's tough for a hobbyist programmer to actually hit the limits of his machine without doing something totally boneheaded. This raises a question: Is there a machine (be it a computer or a console) from the past that would be a good learning platform for someone that has never touched low-level code? I'm very much looking at this from the perspective of someone that wants to understand exactly how to get the best out of the specific set of hardware a machine has.
I'd imagine that the internet probably has manuals for most well known older machines, and it shouldn't be too hard to find an emulator of some sort either. I'm just at a little bit of a loss when it comes to actually choosing a good platform to go for. Any ideas?
Obviously if someone has ideas that don't fit the exact parameters of the question, I'm open for that as well.