mod_backhand is a load balancing module for Apache. It provides per-request HTTP redirection within a heterogeneous Apache server cluster. Each request is processed and run through a set of "candidacy functions" to determine which server is best suited to respond. The request is then proxied to that server. Facilities are in place to allow you to write your own dynamically loadable decision making algorithms. Everything about the request and the current availability of resources can be used in the decision-making process.
auth_ldap is an LDAP authentication module for the Apache Web server. Auth_ldap has excellent performance, due to its use of aggressive client-side caching algorithms. It also has support for LDAP over SS or TLSL. It also features a mode that lets Microsoft Frontpage clients manage their Web permissions while still using LDAP for authentication.
Alkaline is a full-featured standalone search and index server. The spider is a fully remote indexing daemon which includes support for all standards like robots.txt and "skip" meta tags, and allows multiple distinct configurations and search groups (searching many different sites from your server), including complex regexp indexing paths, authentification, filters for various document formats, XML-based online management and statistics, mrtg-compatible perf numbers, and more.