  A few key properties of the World-Wide-Web (WWW) has been established
indicating the lack of any characteristic scales for the WWW, both in its
topology and in its dynamics. Here, we report an experiment which quantifies
another power law describing the dynamical response of the WWW to a Dirac-like
perturbation, specifically how the popularity of a web site evolves and relaxes
as a function of time, in response to the publication of a notice/advertisement
in a newspaper. Following the publication of an interview of the authors by a
journalist which contained our URL, we monitored the rate of downloads of our
papers and found it to obey a $1/t^b$ power law with exponent $b=0.58\pm 0.03$.
This small exponent implies long-term memory and can be rationalized using the
concept of persistence, which specifies how long a relaxing dynamical system
remains in a neighborhood of its initial configuration.
