It took some doing to get the awesome multi colored painting on a T-shirt, but here it is: 'By Lyre and Lightning'  by Mike Kucharski!

 
You can order our merchandise directly from the Ambercon store at Cafe Press and have it shipped wherever you want, but you do pay shipping and handling (and possibly sales tax).
 

The shirt is available in a wide range of styles and other colors (but, honestly, get it in black!) and, we also have a tote bag with the design.
 

Here is a large (2MB, 1000 pixels) version of the artwork.  If the lightbox doesn't work for you, here is a page with it.