Here are some I did for my buddies wife. The thought was to simulate fire, since she has been known to start some.....un-intentionally.
These were double swirled. I dipped in Bohning orange, then swireled with bohning red and bohning black.
To swirel dip, just drip your paint on top of a container of water, GENTLY swirel it around with a toothpick or the like, and dip the shaft through it, twisting as you go. Air bubbles are fairly common, but with practice, you can minimize them.
Jim Rebuck of J and M Traditions put out a DVD that shows you the process. Shows alot of other stuff as well. I dont know who the first was to do this, but Jim seems to have it perfected.
BP