QuickTime editor

Within the track content area, select sample in upper/lower track in the timeline	or
Within the track content area, select next/previous sample in the timeline	or
Within the list area of the timeline, select the upper/lower track	or
In the Track Ruler Area, step backward/forward	or
Drag & copy keyframe sample of a sprite	-drag in Content Area
Create keyframe sample of a sprite	-click
Drag & Copy Track	-drag in List area
Select next time marker	+ or
Open/close tracks, subtracks	+ or
Scale sample time	-drag
Jump to start/end of movie in timeline	+ or

Command Shift Option Key