  In the e-commerce world, the follow-up of prices in detail web pages is of
great interest for things like buying a product when it falls below some
threshold. For doing this task, instead of bookmarking the pages and revisiting
them, in this paper we propose a novel web data extraction system, called
Wextractor. It consists of an extraction method and a web app for listing the
retrieved prices. As for the final user, the main feature of Wextractor is
usability because (s)he only has to signal the pages of interest and our system
automatically extracts the price from the page.
