Dancing lights (star-like) above atlanta, fast, erratic, playful, above clouds, 35 minutes

Ironically, after our media registration for Dragon*Con, I received a call from my intoxicated significant other, claiming there were lights "not moving like planes! what ARE they?!?1" etc etc... As a mechanical engineer, and a long-term skeptic, I promptly rushed to her aide, understanding that she was entranced by satellites or mesmerized by underlit bats.
Much to my surprise, at my arrival at SunTrust plaza, located at Peachtree & Baker, I watched as what appeared to be stars swirled and danced, diving into one another, playing in my indigo southern sky.
The lights that differed from stars only in their locomotion and lack of twinkling, were clearly above the cloud level, as they frequently would dim or disappear behind the occasional lazily passing cumulus.
I can find no rational explanation for these playful sources of lumination.  From aircraft to projections, from critters to carefully-mounted LEDs, my scientific mind boggles at the concept.  They would rush from one end of the sky to the other in seconds, turn back, swirl curved paths, and even hover on the spot.