FSA K-Force Light compact crankset: 170mm 52-38 $250
FSA K-Force Light crankset, no bottom bracket, like new condition (used only on a floor display bike). 110mm BCD, 170 mm crank length, no bottom bracket. K-Force Light is the lightest crankset used regularly in pro cycling.
I ebay'ed it on impulse, but decided to stick with my tried and true Rival, for which I already invested in ceramic bearings.
You'll need an FSA Mega-Exo bottom bracket, AFAIK. The ceramic version retails for $200 or so, with the conventional one around $70.