SWeTE is an HTTP reverse proxy that provides website translation. You can set up proxies for any sites, then connect a translation memory to the site to have it translated into any language. It provides a web-based translation form, and an option to translate strings using Google's translation API.
jRevProxy is a lightweight reverse proxy server fully written in Java. jRevProxy accepts HTTP and HTTPS requests and translates these into new requests based on a set of rules. HTTPS with client side authentication (X509 certificates) is supported.
Oroena is a fully Java 2 Enterprise Edition powered Open Source Reverse Proxy engine. It provides unique session, security or server access management for a multi-server architectured portal.