Panta Rei ... saw this on a license plate during my commute one day. Pretty cool.
Then, a week later, I saw it in the parking lot where I work.
Rheology (/riːˈɒlədʒi/; from Greek ῥέω rhéō, 'flow' and -λoγία, -logia, 'study of') is the study of the flow of matter, primarily in a liquid state, but also as "soft solids" or solids under conditions in which they respond with plastic flow rather than deforming elastically in response to an applied force.