HAproxy is a high-performance and highly-robust TCP/HTTP load balancer which
provides cookie-based persistence, automatic failover, header insertion,
deletion, modification on the fly, advanced logging contents to help trouble-
shooting buggy applications and/or networks, and a few other features. It uses
its own state machine to achieve up to ten thousands hits per second on modern
hardware, even with thousands simultaneous connections.

WWW: http://haproxy.1wt.eu/