We use monthly US utility patent applications to construct an external instrument for identification of technology news shocks in a rich-information VAR. Technology diffuses slowly, and affects total factor productivity in an S-shaped pattern. Responsible for about a tenth of economic fluctuations at business cycle frequencies, the shock elicits a slow, but large and positive response of quantities, and a sluggish contraction in prices, followed by an endogenous easing in the monetary stance. The ensuing economic expansion substantially anticipates any material increase in TFP. Technology news are strongly priced-in in the stock market on impact, but measures of consumers' expectations take sensibly longer to adjust, consistent with a New-Keynesian framework with nominal rigidities, and featuring informationally constrained agents.