From the ACM SIGGRAPH, Vol.32 No.2 May 1998: Game Graphics During the 8-bit Computer Era – a look at what was possible when all you had for graphics hardware was a large rock and a piece of chalk operating at 2MHz, some of the hacks that were used to squeeze the very last drop of functionality out of those systems and some of the more notable games insofar as their graphics.
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Terrific read, that brought back some memories; I remember messing about with raster interrupts on the C64. There are people out there still writing games for these 8-bit platforms.