Meandering of liquid rivulets on partially wetting inclines
  This fluid dynamics video illustrates recent advances in the understanding of the mechanism which causes the sinuous path formed by liquid rivulets on partially wetting inclines. The images themselves show how a simple lighting set-up using a large Fresnel lens can be used to obtain high contrast images of large transparent objects. 
St\'ephanie Couvreur and Adrian Daerr
physics.flu-dyn