One of the fun 'first' projects in most FPGA classes is building a simple VGA display. What is interesting is that a period specific graphics display for the Z80 would probably be something like Cromemco Dazzler[1] with its 32 x 32 pixel color display, or the Super Dazzler.
Linus Akesson ('lft') is probably one of the hackers I admire the most. In a few years he went from a sound-only demo on an ATmega [1], via generating VGA [2] and PAL [3] video demos on the same platform up to implementing custom digital logic including a processor and shader-based graphics accelerator on an FPGA [4].
At the same time, he is a really talented musician, and uses his hardware knowledge to augment [5] and build [6] custom instruments.
He just keeps churning out concentrated awesomeness and hackery.
[1] http://en.wikipedia.org/wiki/Cromemco_Dazzler -- yes I owned one of these boards at one time :-)