I just discovered this last night.
The Freedom From Religion Foundation has started an "Out of the Closet" Campaign, encouraging nonbelievers to publicly state their non-belief. It looks like this was started back in 2011, but I just found it and it is still going on, so why not, right?
The Campaign allows you to build your own virtual billboard from a template, where you can add your photo and a quote and your name and your preferred identifier.
