If anyone was geeky enough back in the late 80’s / early 90’s you remember demos.
For those who weren’t so lucky, demos are small graphics / sound demonstrations. No real purpose or meaning, just doing stuff that made you go “cool”. A lot of the prime game developers no doubt cut their 3D teeth on Amiga & C-64 demos back in the day.
Demos arose out of the warez scene. Basically, they started as small boastful intros at the start of cracked games to announce who cracked what first. Then they morphed into a scene of their own, with groups forming. Then came the gatherings, when groups would participate in contests to create the coolest demo, usually with some constraints.
As the demo scene evolved, the technology has gone with it. Languages started with Assembly, then C, C++, then Java. APIs started to be utilized, like OpenGL & DirecX.
Now, a new breed of demo developers are using a rather interesting tool: Flash.
Check out an example here
Goolge PC Demos and you should find some more interesting demos out there, covering a range of styles, and topics.