As a GC, which materials do you let the subs purchase?

[Daniel Alfandre]

I'm going to build a house.  When I worked as a construction manager for a homebuilder several years ago, we ordered the lumber, windows, doors, stairs/railings, garage doors, trim, cabinets, lighting, appliances, vanities, floors, paint, and other finishes.   We let the mechanicals (elec, plumbing, HVAC) provide the wires, tubes, duct, etc. for the rough-in stuff.  Any other material-management approaches anyone's taken that works well?