For the curious, here is what powers our website: All of our servers run Debian Stable with native IPv6 unless specified.

Frontend Web server

• Django 1.3
• Apache 2.2 with mod_wsgi
• nginx (SSL termination, reverse proxy and serving static files)
• jQuery
• Flowplayer

Database Server

• PostgreSQL database with PostGIS geo-spatial extensions

Development and Asynchronous Job Server

• Exim
• ClamAV
• FFMPEG
• Django 1.3
• Apache 2.2 with mod_wsgi and DAV/svn
• Trac

Development Tools

• Subversion
• Photoshop
• GIMP
• vim
• Dreamweaver

Backups

• FreeBSD with ZFS snapshotting

Statistics

As of 8th April March 2012, we are handling in roughly 200,000  HTTP requests per day (100,000 of which are dynamic) and send approximately 2GB of traffic per day.