Wget is a command-line Web client. It supports recursive retrievals and HTTP proxies.
If you want to test your Squid cache in batch (from a cron command, for instance), you can use the echoping program, which will tell you (in plain text or via an exit code) if the cache is up or not, and will indicate the response times.
David Marwood and Brad Duska have some cool Squid Proxy Analysis software.
SQUIDTIMES by Nico Tranquilli.
Kenichi Matsui has a simple perl script which generates a 3D hierarchy map (in VRML) from squid.conf. 3Dhierarchy.pl.
transproxy is a program used in conjunction with the Linux Transparent Proxy networking feature, and ipfwadm, to transparently proxy HTTP and other requests. Transproxy is written by John Saunders.
A redirector package from Iain Lea to allow Intranet (restricted) or Internet (full) access with URL deny and redirection for sites that are not deemed acceptable for a userbase all via a single proxy port.
Junkbusters Corp has a copyleft privacy-enhancing, ad-blocking proxy server which you can use in conjunction with Squid.
Squirm is a configurable, efficient redirector for Squid by Chris Foote. Features:
Pedro L Orso has adapated the Apache's htpasswd into a CGI program called chpasswd.cgi.
jesred by Jens Elkner.
squidGuard is a free (GPL), flexible and efficient filter and redirector program for squid. It lets you define multiple access rules with different restrictions for different user groups on a squid cache. squidGuard uses squid standard redirector interface.
The Smart Neighbour (or 'Central Squid Server' - CSS) is a cut-down version of Squid without HTTP or object caching functionality. The CSS deals only with ICP messages. Instead of caching objects, the CSS records the availability of objects in each of its neighbour caches. Caches that have smart neighbours update each smart neighbour with the status of their cache by sending ICP_STORE_NOTIFY/ICP_RELEASE_NOTIFY messages upon storing/releasing an object from their cache. The CSS maintains an up to date 'object map' recording the availability of objects in its neighbouring caches.