Redis - Redis is an open source in-memory data structure project implementing a distributed, in-memory key-value database with optional durability.
CCProxy - Want to share Internet connection? Get every computer online through a single Internet connection?
memcached - High-performance, distributed memory object caching system
Apache Traffic Server - Fast, scalable and extensible HTTP/S 2 and 1.1 compliant caching proxy server.
Aerospike - Aerospike is a high-performing NoSQL database supporting high transaction volumes with low latency.
3proxy - 3proxy freeware proxy server for Windows and Unix. HTTP, SOCKS, FTP, POP3