Our ductless mini-split HVAC system is in the process of being hooked up this week. We made this decision a long time ago because it seemed like the best compromise between performance, efficiency, cost and appearance. We're very excited not to have soffits for ductwork (other than bath & dryer vents) anywhere in the house! The system has compressors outside like traditional central air, but instead of ducts running around the house, there are tubes for coolant, power and condensate that run behind the walls to wall-mounted units. Our wall-mounted units happen to look like picture frames, and when turned on they tilt open and begin blowing air. Eric says they are like transformers - I haven't seen one in action yet. These are very popular in Europe, not sure why it hasn't caught on more here. We also have some ducted ductless portions of the system (I know this sounds funny), but this equipment is all mounted in our bathroom ceilings and air pours out into the surrounding rooms, so we have 8' ceilings in the bathrooms, but 9'+ everywhere else. We also have 7 zones so we have tight control over the temperatures everywhere!