Signal transduction pathways are complex coupled sets of biochemical reactions evolved to transmit and process information about the state of the immediate cell environment. Can we design experiments that would inform us about the properties and limitations of signal processing? Recent studies suggest that this indeed can be achieved by exciting a cell with carefully designed oscillatory stimuli. Although this analysis has its caveats, complex temporal stimulation of signal transduction networks can serve to rapidly advance our understanding of these information channels and ultimately create intelligent ways of controlling them.