Dark Hot Giants are so hot that dark sodium haze appears, making the planets pitch black and featureless. Here is a list of Dark Hot Jupiters that appear at Extrasolar Visions. For an updated list, see Dark Hot Giants.
HD 49674 System - Contains the first planet found to have significantly less mass than Saturn.
HD 179949 System - Contains the first planet discovered by the Anglo-Australian Planet Search, which is also the first exoplanet whose Magnetic Field was observed. This Hot Jupiter is about the same mass as Jupiter and orbits once every thre days. It was found to have supersonic winds that caused the night side (not tidally locked) to be as hot as the day side. This system is also the first observed to have planet-induced stellar X-ray activity. Magnetic interaction causes a bright spot on its star at 30 degrees latitude.
HD 217107 System - Contains the first discovered moderately eccentric Hot Jupiter. Its outer planet was suspected when the inner one was discovered due to its eccentricity (0.13) and confirmed with four other new multiplanet systems in 2005. The Outer planet c is highly eccentric and skirts the outer edge of the habitable zone.