D'oh, I kept forgetting... check out photoshop brushes by Deviney. He has a set of 'Skulls' somewhere -- I forget if it's here, or DAZ, but it's a great pack. I've bought from him frequently on both sites and never regretted a single one; they're amazingly useful and he does a really great job with them. It has a lot of fantastic options for tattoo designs, as it also includes a number of 'background elements' that are tribal designs, lightning, etc. so it's not just a pile o' bones. :) (I totally blanked on the existence of this one until I just had to use it for something myself.)

It would likely come in very handy for goth or rock tee shirt designs as well, so it may be a good investment to use for both packs, as well as future uses!

-D
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It's all fun and games until someone loses an eye texture.