Squid

Squid is:


 * a full-featured Web proxy cache
 * designed to run on Unix systems
 * free, open-source software
 * the result of many contributions by unpaid (and paid) volunteers

In other words, squid can be set up to download and cache websites for you to save on your bandwidth. You can also change / block / redirect pages. For example you can get some pages to automatically pick the 'print' option, or block ads. This is all done via the squid.conf file found in /etc/squid.

Squid supports:


 * proxying and caching of HTTP, FTP, and other URLs
 * proxying for SSL
 * cache hierarchies
 * ICP, HTCP, CARP, Cache Digests
 * transparent caching
 * WCCP (Squid v2.3 and above)
 * extensive access controls
 * filtering of unwanted web content with ufdbGuard
 * HTTP server acceleration
 * SNMP
 * caching of DNS lookups