Most of us have probably seen skywriting, but a new company has a twist to it, man made clouds in the form of corporate advertising that can look just like the logos. The “flogos” are made from a chemical surfactant and helium and can last for up to a half an hour.
I kinda liked Armageddon’s solution (in the comments).
image: “Let’s” in Skywriting, Prints &
Photographs Division, Library of Congress