It must be the combination of the steel grey palette, the black accents, and their patches and rivets, but these two A-10s look especially cool and futuristic to me in this photo. Like they can be piloted by this guy.
Perhaps it's because this aeroplane has become such a design icon that it has already transcended its own time. I can't remember any other plane so ugly that became so beautiful so quickly. Perhaps the original Thunderbolt, which was so chubby compared to the P-51 Mustang and other planes of that era. Look at this amazingly beautiful beast now:
But while both look equally burly, the original Thunderbolt wasn't as deadly as the Warthog, which was built around a gun two times the size a Volkswagen Beetle -- the 30mm GAU-8 Avenger, the biggest gun ever in a combat jet.
The top photo is by Master Sgt. Becky Vanshur for the National Guard. You can download the full resolution photo here.