A couple inspirations for the design:
The above T-Shirt design for Dave Matthews Fall 2007 tour was done by FarmBarn Art Co. It appeared in Print Magazine's design annual, which has worn pages after doubling as my reference book for the past couple years. I think it's a pretty sick nasty design. (Sorry, choppy pic taken with my cell phone)
The above graffiti art is done by artist, illustrator and hip-hop musician, Kid Acne. An eye-popping design by an all-around creative dude. It appeared on his blog, which is pretty impressive, but check out his music too. Although, I can't figure out what nationality he is. He sounds like a Piker from the movie "Snatch."