SDW remade one of his old GP32 demos for PSP, this one is “Minimalistic Crap”.

A demo is a non-interactive multimedia presentation made within the computer subculture known as the demoscene. Demogroups create demos to demonstrate their abilities in programming, music, drawing, and 3D modeling. The key difference between a classical animation and a demo is that the display of a demo is computed in real time, making computing power considerations the biggest challenge. Demos are mostly composed of 3D animations mixed with 2D effects and full screen effects. (taken from Wikipedia)