The Lucid website is a really well done project site. It features a custom-tailored package repository, and download apps. This was one of my earlier works, so it's a bit rougher, but it's still fairly impressive.
I didn't create the design for this, but I wrote custom Django apps and make use of existing Django apps to create the final site. The package and downloads sections consist of purely my code.
The package repository allows developers to upload their apps for Lucid to the repository, as well as provide screenshots and additional information about the app. It also allows developers to release new versions of their apps. Users can subscribe to new releases via RSS. There is also a voting system in place, so users can rate packages based on which ones they like the most. Most of the information for the package is read from the package file itself (such as the version, etc.), so developers can upload packages with ease, while ensuring that their application's system name doesn't overlap with another package's.
The downloads app was written from scratch. It streamlines the release of new versions of Lucid. Lucid actually pings this app to check to see if it's up to date.
I used a few existing apps in the site; I used a modified version of the blog app used on Django's site for the blog section, Snapboard for the forum, and the app used on Django's documentation site for the documentation.
The site also auths against an LDAP server that the Dojo Foundation uses. This way, anyone who has already registered on Dojo's site can log into Lucid's site.