Using VidSync as an Event Logger
Although VidSync was developed for measuring things on video, its measurement organization features are also very useful for simply marking, browsing, retrieving, and making notes about relevant observations, without trying to measure anything.
You can use VidSync for event logging with one video, or with multiple synchronized videos. To use VidSync's advanced playback features with one video, you have check the box for "Show advanced playback controls with only one video clip loaded" in VidSync Preferences in the File menu, under the "Misc" tab.