Context module provides context for elements, that can be conditioned and triggered. It works with devseed Admin module. When with jQuery UI and an Admin module, it will produce draggable interface (inline context editor).
Purl is a library for capturing and abstracting a request handling that goes beyond Drupal's standard functionality. It catches things like path prefix, user agent, subdomain - and systains them in a form of a path prefix or suffix. Any part of request can thus be sustained.
Like a langauge prefix in i18n. As you continue browsing, the language prefix preserveres but is stripped from the Drupal arg(); system before it reacts to it.
Spaces is a library that allows to customize settings based on a specific context - og, user, etc. When customization in a specific space is made, its values override the generic values of a configuration object. Configuration objects can be variables, contexts, and views. Not nodes, users, taxonomy, blocks values.
Spaces can have presets - templates that can be reapplied.