In July 2011 Yahoo terminated the web service BootCaT used to search the web; after a few days of blackout, BootCaT is working again thanks to Bing, a search engine that still provides free access to its search API.
collect_urls_from_yahoo.pl has been moved to the outdated_scripts directory; a new Java command-line program is now used to collect URLs from a search engine, UrlCollector.jar; the new program provides almost all the functionalities of the old script and adds a couple of new ones, use java -jar UrlCollector.jar -h to read the documentation