Traffic Server is fast, scalable and extensible HTTP/1.1 compliant caching proxy server. Formerly a commercial product (created by Inktomi, later acquired by Yahoo!), it is now being developed as an Apache Incubator Project

Redis is a key-value database. It is similar to memcached but the dataset is not volatile, and values can be strings, exactly like in memcached, but also lists and sets with atomic operations to push/pop elements.

Beaker is light WSGI middleware layer that provides session's using Myghty's Container API.

Gears is an open source project that enables more powerful web applications, by adding new features to web browsers.

The goal of this project is to provide a system for storing and retrieving huge amounts of data, distributed among a large number of heterogenous server nodes, under a single virtual filesystem tree with a variety of standard access methods. Depending on the Persistency Model, dCache provides methods for exchanging data with backend (tertiary) Storage Systems as well as space management, pool attraction, dataset replication, hot spot determination and recovery from disk or node failures. Connected to a tertiary storage system, the cache simulates unlimited direct access storage space

MogileFS is an open source distributed filesystem

apt-cacher.pl is a CGI which will keep a cache on disk of Debian Packages and Release files (including .deb files) which have been received from Debian distribution servers on the Internet. When an apt-get client issues a request for a file to apt-cacher.pl, if the file is already on disk it is served to the client immediately, otherwise it is fetched from the Internet, saved on disk, and then served to the client. This means that several Debian machines can be upgraded but each package need be downloaded only once.

memcached is a high-performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load.

nginx [engine x] is a HTTP server and mail proxy server