Work Wheels Japan has their own line of lug nuts suitable for all aftermarket wheels with a 60 degree conical seat. They are high quality with buttery smooth threads matched with awesome machining and colors.
 
These are the RS-R Type open version, meant for cars with extended studs and owners wanting to shed every last gram of weight. They are made of lightweight T6-7075 aluminum and available in M12x1.25 or M12x1.5. Colors availble are black, blue, red, gold, green, and purple anodizing.
 
NOTE: Do NOT use an impact wrench on these.