Nothing has changed since 30 years ago. Huge part of the 8-bit demo scene grew around exactly 'illegal and undocumented' CPU instructions, allowing kids (at the

Nothing has changed since 30 years ago. Huge part of the 8-bit demo scene grew around exactly 'illegal and undocumented' CPU instructions, allowing kids (at the time) to come up with some really crazy and awesome stuff, given on paper capabilities of hardware like 6500/6502 in C64 and other machines (think opening screen borders, think more than 8 sprites, think more than 256 colors in hi-res and many more).