Happy System was a computer store, they built custom computers and imported high-end components.
My customer was fxed on the idea of using yellow and purple so that was a direct requirement, fortunately, yellow is considered to speak of happiness so that was a good start.
We discussed about reaching an image being playful and informal. I played with the idea of a stack of boxes, just like the components were shipped in, then put a happy face on a monitor sitting diagonally over the boxes. My client loved it.
The logo appeared every weekend on their newspaper ads, and was also put on a large luminous sign atop his shop's roof. It was also turned into a square decal and was put on each of his products. Alhought the company closed some years ago struggling in a tough market, I still keep one of those decals on my computer.