Kupfer is an open-source, powerful and flexible desktop search tool for Linux and other Unix-like operating systems. It is designed to help users quickly locate and launch applications, documents, and other files. It is a highly configurable application launcher that can be used to quickly find and launch programs, files, web searches and more. It is based on a powerful Python engine and has a plug-in architecture that allows users to extend its functionality. Kupfer is fast, lightweight and has a simple, intuitive user interface that allows users to quickly find what they need. It can be used to quickly launch applications and documents, search the web, and more.
Fast, beautiful, configurable. Not so many add-ons, but you can live with it. Already packaged for Ubuntu.