[madetoshareqs]

Quicksilver is most excellent! I made this account to share it before I saw this comment.

I have used it for a decade. I use it primarily as a launcher but it supports a usage model of select thing then select action to perform on the thing which makes it a versatile and powerful way to drive things by keyboard.

It also has a plug-in system with integrations for other apps.

I recommend the Yosemite theme. https://github.com/mikker/YosemiteDarkInterface-qsplugin