Congealing useful oddballs

Many microsystems manipulate tiny quantities of liquid to conduct chemical reactions or biomedical investigations. In a new twist on such technology, engineers at North Carolina State University in Raleigh have adapted a microfluidics device to fabricate tiny, solid balls of various patterns that could serve in applications ranging from drug delivery to electronic displays.

GOLDEN GAZE. Gold particles spontaneously clump together, irislike, at the center of this 1-millimeter-diameter polystyrene ball.