Obama Lady Gaga
According to the White House pool report filed by Carol Lee of The Wall Street Journal, Gaga's hairdo and heels made her at least eight feet tall:
At 8pm pool was brought through the house, where Poker Face by Lady Gaga was playing, and into a white party tent set up in the back of the house. There were 7 large round tables - three on each side and one square in the middle in front of a small open space with an American and California state flag set up, where President Obama spoke.
At 8:03 pm Lady Gaga entered... delicately walking on sky-high heels (she towered over everyone, a good 2 feet taller than POTUS). She was wearing a floor-length sleeveless lacey black dress, her blonde hair was gathered in a bouffant up-do adorned with a black hair piece with a black veil down the back, which she swept to the side and in front of her left shoulder. (The hair added about 6 inches to her stature). She took a seat at the middle table in the tent and stood up with the other guests when POTUS entered a few minutes later.
Event was print pool only so no press photos.
POTUS spoke for about 8 minutes, with Lady Gaga sitting front and center. And although he never acknowledged her obvious presence, it seems likely the two crossed paths during greetings inside the house before the dinner.