Pimcore is a Zend-powered PHP content management system/framework.

Pimcore sports enterprise-scale features, such as advanced data management, A-B testing and tools for app development.

It’s especially useful for e-commerce solutions as it features product information management. All in all, Pimcore looks like a splendid alternative to pre-made platforms, because of the customization and rich array of features it has.

Letterpress is a small and fast blog engine written in Python.

Letterpress uses text instead of databases — more safe, but less fun stuff to do — and uses Markdown for generating the files.

This blog engine comes with a number of useful features, such as an archive, tags, and soforth. You can use DropBox for publishing.

Mueller is a grid system for responsive and non-responsive layouts.

It uses Compass and gives users full control over column width, gutter width and baseline grid.

Mueller sports a number of module-based features, and is specifically aimed at those who aren’t afraid of coding and know how to write in Compass.

Mueller is intended for general use, but definitely not for creating fluid designs.

Maki is an icon set for web maps, consisting of 219+ icons.

The icon set is great for maps — whether you want to pinpoint some locations of note on a map or simply want to mark public transportation.

The icons come in three sizes of .PNG and .SVG; they scale up elegantly and are released under the very liberal BSD license.

voxel.js is a game building toolkit for creating voxel (Minecraft-like) games for browsers.

Voxel.js is of a modular build with only three essential components; other modules add functionality. As of now there are modules for, e.g., multi-player and creating creatures and forests.

From the demos it looks rather demanding on the performance, but hopefully things can be tweaked in the next releases.

Grappelli is an admin interface for Django that features a consistent and grid-based look & feel.

Grappelli enhances the default admin interface functionality of Django with several database- and style-related tools.

Among the most impressive features are autocomplete integration, TinyMCE themes, improved collapsibles and Compass-based stylesheets.

You only need to know Python for operating Grappelli and Compass for customizing the styles.