What is the origin or derivation of the phrase "greasing the skids?"
The phrase connotes preparation, in such a way as to make the subsequent activities easier. Definitions are available various places (e.g., The Free Dictionary, Askville). The latter suggests a derivation (or derivative) "skid row" without citation.
I had always assumed the derivation of "skid" (that which is being "greased" in this sense) was a rather literal description of lubricating pallets or skids for moving or sliding them, or a skidder machine, but I can't find any good reference.
This blog suggests two other derivations that are somewhat similar: greasing the parts of a winch system over which items would be dragged, or in shipbuilding to grease the parts along which a newly-constructed ship would slide into the water.
Other phrases are at least superficially similar but perhaps unrelated, such as greasing the pan (but seeming to connote a specific, necessary prerequisite; in fact a comment on this answer also refers to "skid greasing"), or greasing palms (connoting bribery).