I'm working on "Merry Fitzmas" gear - open to suggestions

UPDATE: I've changed the base of the "Fitzmas Tree" below and changed it to "Merry Fitzmas."

I'm open to suggestions for Fitzmas gear to sell, but keep the following requirements in mind:

1. I don't do graphics. So I can't draw pictures of things.
2. Anything I use in the shirts/products needs to be public domain (meaning, we can only use photos that are on .gov Web sites, photos that YOU OWN and give us, or photos on sites that say outright that they're public domain).
3. Images, graphics etc need to be at least 150 dpi, but preferably 200 or 300 dpi. Typically, I use a 10 inch by 10 inch, 300 dpi canvas for creating the shirts, for example (that's a good template to use across the board).

So, those are my constraints. If anyone wants to design any shirts and offer ownership of the designs to the blog as a contribution, they'd be most welcome (keeping in mind that we'll need to make the final decision as to whether we like the design enough to run with hit.) Also, feel free to simply suggest Merry Fitzmas shirts as well, meaning, even if you can't design anything you can describe the shirt in writing in the comments.

Here's my first attempt at a Merry Fitzmas product.