I haven't tried them, but on another group this receipe for alcohol inks was posted, and I thought I'd pass it along...
"Add one package of powdered Rit dye to a small baby food jar....then add rubbing alcohol to the top of the jar, and shake well. Another way I've done it is to take a black film canister, fill that about 1/4 of the way with the powdered Rit dye, then fill the rest of the canister up with the rubbing alcohol, and shake. I've found this to work really well"