Dr Raskar and his students are working with one that fires its pulse in a quadrillionth of a second.
From the economist.com
A femtosecond is one quadrillionth of a second.
From the sciencedaily.com
Changes in the electron cloud can happen on timescales of less than a femtosecond, or one quadrillionth of a second, representing some of the fastest processes in the natural world.