Shotcut is a free, open-source, cross-platform video editor
I've been using it to create a 1min teaser trailer. The UX is mostly good, though at times atrocious; the Undo/Redo implementation isn't 100% there, frustratingly; the audio always stutters when beginning in-editor playback. However, it seems to be working great for most of what I want to accomplish, including some decent keyframe support for certain filters.