Finding a place with exposed ductwork is like the holy grail for industrial types–you've found something that totally speaks your style, and now you need to know what to do with it. Or maybe you're reading this because exposed ductwork isn't your taste, but you are living with it, and you want to find a way to hide the ducts and pipes running through your otherwise great apartment.
For either of the situations above, the answer lies in one of these three solutions:
Paint Them the Color of the Ceiling
If the ceiling's white, give the ducts a matching coat, as shown in the example above. Same goes for any other shade (or if the ducts mostly overlap a wall, paint them that color). If the ceiling is raw wood or brick, bring some paint chips home and try to match a dominant shade. The idea here is to make the ductwork disappear, visually.
Above: Even dominant ductwork can fade into the background, as seen in this Washington D.C. condo from Design Milieu via Houzz.
Paint Them an Eye-Catching Color
Treat the exposed hardware like an accessory for your room, and give them a colorful coat of paint that matches something else in the room–or doesn't. This helps to camouflage their industrial side without totally making the ducts disappear.
Leave Them Au Natural
Last but not least: Leaving ducts and pipes bare is the most common thing to do–and also the easiest. Just do... nothing. Leave your ductwork just as it comes and enjoy a space that has a raw, industrial vibe.