still can't find the write up on Heckmann, I'll have to write to Shawn and see if he can resend it to me... in the meantime http://www.nytimes.com/2011/02/27/us/27gas.html?pagewanted=1&_r=2&hp&adxnnlx=1298826128-YAMtPM4jYghbkjg9Q26Ktw http://ts2.mm.bing.net/images/thumbnail.aspx?q=604835229301&id=913ba1a0f4c0267b1ef6b9cd03980d43&url=http%3a%2f%2fwww.math.tamu.edu%2f%7etom.vogel%2fcalc3d.gif