A Golden Orb Weaver (Nephila edulis) is sedated with carbon dioxide gas, and pinned around her limbs and abdomen, keeping her in place without causing any harm. Silk is pulled by tweezer from the spinnerets and attached to the spool with a dab of glue after which the motor is started to begin harvesting. The silk produced here consists mainly of major ampullate silk which forms the main structure of the web (like scaffolding) and minor ampullate silk, which is used to form the main spiral of the spider's web. Nephila edulis females can produce up to six different types of silk.
It's possible to harvest between 30-80 metres of silk in one go, after which the spider can be released back to its web to feed ready for reeling another day.
Incidentally, this is also Facebook's business model: