Apache mod_suid allows per-vhost execution of scripts under their own UIDs. It functions in a way similar to Apache's perchild MPM, but differs in a number of ways. It does per child user/group switching; the Apache MPM makes switches based on vhosts. All processing is done under a specific UID/GID, including PHP and mod_perl scripts.
uIP is probably the smallest implementation of the TCP/IP protocol stack ever written in a high level language; the code footprint is on the order of a few kilobytes and RAM usage is on the order of a few hundred bytes. uIP is intended to be used in embedded systems running low end 8- and 16-bit microcontrollers.
RabbIt is a mutating, caching Web proxy used to speed up surfing over slow links like modems. It does this by removing advertising and background images and scaling down images to low quality JPEGs. RabbIT is written in Java and should be able to run on any platform. It does depend upon an image converter if image scaling is on. The recommended image converter is "convert" from the ImageMagick package.
mod_layout is an Apache module that provides both a Footer and Header directive to automagically include output from other URIs at the beginning and ending of a Web page. It can be used to wrap documents for a standard look and feel for a site (or to insert banners on any given document in a site). Currently known to support mod_perl, PHP and Apache JServ. Should support just about any type of handler.
mod_ssl provides provides strong cryptography for the Apache 1.3 webserver via the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1). It is based on the SSL/TLS toolkit OpenSSL and supports all SSL/TLS related functionality, including RSA and DSA/DH cipher support, X.509 CRL checking, etc. Additionally it provides special Apache related facilities like DBM and shared memory based inter-process SSL session caching. per-URL SSL session renegotiations, DSO support, etc.
MultiLoad is a load balancer that redirects HTTP requests to pre-defined servers/locations. It gives the provider a way to balance the traffic and hides the real download location. It allows you to manage different version of each download. It is also a load balancing server extension. You can distribute files on some servers so that a downloaded file can be loaded form different servers. These servers can have different priorities to control the active traffic.