Crazy Dog out of Rochester, NY (where I was born!) has a t-shirt version of the traffic congestion signs that were “repurposed” to warn of zombie attacks, which I think is pretty cool.
They also have what has to be the most obscure zombie sub-reference on a t-shirt ever:
To get this, you have to remember that the name of the trucking company stenciled on the side of the trucks used to barricade the entrance of the mall in the original Dawn of the Dead was “BP.”
I am both astounded and delighted by the obscurity of this!
To see these and other zombie shirts by Crazy Dog, click here.
ScottKenemore.com 
I love this, definitely got to have both of those tees, esp now that I know what that BP reference is about!! Thanks so much for posting this, it’s great!
Yeah, that BP reference is pretty epic. Makes Simon Pegg’s “Foree Electric” badge in Shaun of the Dead look like a gimmie by comparison.