Eight legs bad. Six legs good.

The UnMuseum - Stop Motion Photography

Harryhausen's six-armed octopus from It Came From Beneath the Sea.
Since producing stop-motion sequences were so labor intensive and expensive, animators often had to find unique ways to cut costs during production. Ray Harryhausen, while filming It Came From Beneath the Sea (right), the saga of a giant irradiated octopus that ate San Fransico, was forced to reduce the number of arms on the octopus model from eight to six to help keep the picture on budget.