http://www.arstechnica.com/articles/cul ... rt-2.ars/2
Jay Miner may have been leading the team, but the details of the new computer were hammered out at team design meetings, held in a seminar-like room that had whiteboards covering the walls. Everyone could pitch for inclusion in the machine, and the small group would have to come to a consensus about which features to include and which to leave out. Engineering is all about tradeoffs, and you can't just decide to include "the best of everything" and have it all work. Cost, speed, time to develop, and complexity are just some of the factors that must be taken into account at this crucial stage of a new computer. The way the Amiga team came to a consensus was with foam rubber baseball bats.
It isn't known who first came up with the idea, but the foam bats became an essential part of all design meetings. A person would pitch an idea, and if other engineers felt they were stupid or unnecessary, they would hit the person over the head with a bat. As Jay said, "it didn't hurt, but the humiliation of being beaten with the bat was unbearable." It was a lighthearted yet still serious approach, and it worked. Slowly the Amiga design began to take shape.
Actually the article series is quite good and interesting for those interested in computer history.