Proof that you can make anything sexy, given the budget: Sydney, Australia-based fabrication studio Kinkfab makes these custom AC vents out of CNC-milled, anodized aluminum.
In addition to their aesthetic appeal, they’ve been designed specifically where wood panels are desired, but cutting a large, contiguous opening (to accommodate a standard vent) would remove so much material that the panel is no longer structural. Kinkfab’s solution allows you to leave more meat on the bone.