Based in the DrawTailBehindMouse composition (in the manual, page 79), but instead of the mouse position, I used the hand position to draw the trail. The Grab command define the thickness (open hand show nothing, you must grab your hand a little: more grab, more thickness.
Its a very simple composition, remixes are more than welcome :)
I'm a very beginner, happy with the 2.0 version...
SwipeGesture A straight line movement by the hand with fingers extended.
ScreenTapGesture A forward tapping movement by a finger.
KeyTapGesture A downward tapping movement by a finger.
Currently, Vuo has limited support for gestures, being able to detect pinch and grab amount with the Get Hand Values node. Might be helpful to add gesture nodes for these, too, as is done in oz.LeapMotion for Quartz Composer.