This Apple Script is a droplet that will open any file dropped on it, and set looping to true before playing it in QuicklTime. It is usefull for opening small videos, for instance from Vine, and loop them.
Start AppleScript Editor, and paste the LoadVid script into it. Compile the script, and save it as an Application (File Format dropdown). Save it into your Application folder (or desktop). Drag the droplet onto your Application Dock.
Drag and drop video files onto the droplet to open video. It works from other applications as well (i.e. dragging videos from iMessage).