MVProc FastCGI is a Model-View-Controller platform that uses MySQL stored procedures as the Controller element. It's based on the stable Apache module MVProc, and all functionality has been tested (and load tested), so it may be "Production Ready" even though it hasn't been implemented in a production environment as yet. Benchmarking indicates it's "nearly as fast" on lighttpd as the MVProc Apache module, though a truly thorough benchmarking with a variety of servers and web applications...
P2P application protocol framework (RFC3080, RFC3081) for connection-oriented, async request/response messages. Allows multiplexing of message streams over one transport connection. Supports binary and textual messages, TLS, SASL/Anonymous, SASL/OTP.
A mod_perl-based RPC API designed for ease of setup, ease of extension, and rapiddevelopment.
Using Presto, you can develop a robust, fully "web-2.0" web application in a day or two.
Oh and it scales.
Take that, Ruby on Rails.