yxorp is a reverse proxy and application level firewall for the HTTP protocol. It can do all kinds of checks on HTTP traffic, and is highly configurable. It also has other functions that are useful for a web frontend, like load balancing.
Lemonldap is a reverse proxy based on Apache and mod_perl which manages the accesses of protected resources by informations hosted in LDAP.A webmin module for system administration is provided.
Web reverse proxy for Single Sign On (SSO). It can apply a security policy (profiles stored in a LDAP directory) to an existing set of applications, consolidate websites, encrypt all communications, rewrite simple URLs...