Synapse - Synapse is a semantic launcher written in Vala that you can use to start applications as well as find and access relevant documents and files by making use of the Zeitgeist engine.
Boostnote - Boostnote is an open-source note-taking app.
Gnome-Pie - Gnome-Pie is a circular application launcher for Linux.
Lepton - Lepton image compression: saving 22% losslessly from images at 15MB/s
Gnome Do - Simple, sleek, swift, smart. Do. GNOME Do allows you to quickly search for many items present on your desktop or the web, and perform useful actions on those items. GNOME Do is inspired by Quicksilver & GNOME Launch Box.
3Cols - Manage your code snippets in the cloud fast, easy and free for personal use forever.