Kupfer (reborn): https://github.com/kupferlauncher/kupfer

Fly-Pie: https://github.com/Schneegans/Fly-Pie

Gnome-Pie: https://github.com/Schneegans/Gnome-Pie

Synapse: https://launchpad.net/synapse-project

Launchy: https://www.launchy.net/

Cerebro: https://github.com/cerebroapp/cerebro

Lighthouse: https://github.com/emgram769/lighthouse