BSP: Black Sand Pearl

It is a shorthand for colors.
Also:
BBC: Black Berry Crush
GRM: Gold Rush Metallic
CS or CSM: Classic Silver Metallic
NBM: Nautical Blue Metallic (08-only color)
HTM: Hypnotic Teal Metallic

Others:
Stingray (introduced in 09), I can't thing of another abbreviation or nickname
White or SW: Super White

No one has really abbreviated Absolute Red, or whatever the RS6 red is officially called.