On a car in Illinois there's a pink IPU symbol decal.
The car belongs to Irena. She was brought up very secular. She recently found out that her grandmother was a militant atheist. Irena tried religion for a bit, but it didn't bring her peace like atheism does. "Atheism is liberating and I guess Granma' raised me right", Irena says.
As to why it is the IPU symbol on her car she says. "I have always loved unicorns, because come on it's a unicorn! and then when my friend told me the meaning of the Invisible Pink Unicorn, they became that much more special".
She adds "I actually will be getting a tattoo soon with the IPU symbol tattooed on a unicorns butt".
It was Irenas friend who made her the pink decal.
Redistribution and use of the IPU symbol, with or without modification, for commercial and non-commercial purposes alike, are permitted provided that the IPU symbol is used to represent atheism. Link to downloads here