nginx

nginx [engine x] is a HTTP server and mail proxy server written by me (Igor Sysoev).

nginx has been running for more than three years on many heavily loaded Russian sites including Rambler (RamblerMedia.com).
In March 2007 about 20% of all Russian virtual hosts were served or proxied by nginx.
According to Google Online Security Blog year ago nginx served or proxied about 4% of all Internet virtual hosts, although Netcraft showed much less percent.
According to Netcraft in March 2008 nginx served or proxied 1 million virtual hosts. The growing in picture and color!
2 of Alexa Top100 sites use nginx.
Here are some of success stories: FastMail.FM, Wordpress.com.

The last stable version is nginx-0.6.30, the change log.
The last legacy stable version is nginx-0.5.36, the change log.
The sources are licensed under a BSD-like license.

The English Wiki.

The Russian documenatation.

Basic HTTP features:

Mail proxy server features:

Tested OS and platforms:

Architecture and scalability:

Other HTTP features:

Experimental features: