I don’t remember where I found the link, but I was fascinated by what can happen (YouTube link to the same video) when you pour shampoo or other viscous liquids. The Wikipedia article states that “the surface suddenly spout[s] an upcoming jet of liquid which merge[s] with the downgoing one.” Arthur Kaye first described the phenomenon in 1963, but only a year ago, in April 2006, did a group of Dutch scientists (Michel Versluis et al.) manage to explain the effect. They also discovered a method to create a stable Kaye effect. You can download their article, “Leaping shampoo and the stable Kaye effect.” Michel Versluis et al, J. Stat. Mech. (2006) P07007, here at the IOP, or here.
Really cool!