In general, any Web functional testing tool can be used as a scraper. Scraping and testing are extremely similar. In both cases, one uses XPath or (hopefully) CSS to locate an element and examine certain aspects of that element's state. A scraper is only different from a functional test in that a scraper is focused only on the state of nodes (potentially) containing human-readable content. That, and a scraper saves the data it collects rather than discarding all data at the end of a test run.
Here's a very old Selenium 1.0 example that scrapes the full, rendered HTML of a page. After performing a scrape like this, I would then feed the HTML into a parser such as Nokogiri http://snipplr.com/view/7906/rendered-wget-with-selenium/
Here's a very old Selenium 1.0 example that scrapes the full, rendered HTML of a page. After performing a scrape like this, I would then feed the HTML into a parser such as Nokogiri http://snipplr.com/view/7906/rendered-wget-with-selenium/