punding
n.— «“Punding” is a stereotypical motor behavior in which there is an intense fascination with repetitive handling and examining of mechanical objects, such as picking at oneself or taking apart watches and radios or sorting and arranging of common objects, such as lining up pebbles, rocks, or other small objects.» —“Punding on L-dopa” by H.H. Fernandez, J.H. Friedman PubMed Sept., 1999. (source: Double-Tongued Dictionary)