Software for checking for changes in a web site

[Even Flood]

Folks,

A user asked me about the following: He needs
a client program that monitors a remote website (or several)
and informs him when the page is changed. He wants
to be able to set up the websites he wishes monitored
himself, so it must be a local program - or a website
that does the job for him. Anyone heard of such a product?

Even
Even Flood,  Senior Research Librarian
RBT/Norwegian DIANE Center,
University Library of Trondheim,
N 7491 Trondheim, Norway.
Phone: +47 73 59 51 62, Fax +47 73 59 60 97
http://www.ub.ntnu.no/diane/
"Come, and take choice of all my library, and so  beguile thy sorrow."
				(Shakespeare)