Introduction to writing spiders and agents
cURL
    cURL (client for URLs) is a command line tool for getting or sending files using URL syntax
        http://curl.haxx.se
        http://curl.sourceforge.net
       
    Curl supports a range of common Internet protocols, currently including HTTP, HTTPS, FTP, FTPS, GOPHER, LDAP, DICT, TELNET and FILE
       
    OpenSource (not GPL) and not to be confused with Curl the client-side programming language
        http://www.curl.com