Scrapy is a fast high-level screen scraping and web crawling framework, used to crawl websites and extract structured data from their pages. It can be used for a wide range of purposes, from data mining to monitoring and automated testing.

Samples of Web Scraper using Mechanize, Delayed Job, Parallel, Mongo, etc.

a little urllib2+cookielib for saving cookies with urllib2, maybe for login-required websites.