Timer with less clear/setTimeout calls...

debounce-example.md

$(window).bind('mousemove mousedown mouseup scroll keydown keyup focus', debounce(10E3, function() {
	// idle
}));

debounce.js

// Requires timer.js
function debounce( delay, callback, timer ) {
	timer = timer || Timer();
	
	return function() {
		timer.set( delay, callback, this, arguments );
	};
}

silencer-example.md

$(window).mousemove(silencer(function(e) {
	document.body.innerHTML = '<h1>x=' + e.pageX + ' y=' + e.pageY + '</h1>';
}, 800, 100));

In this example mousemove is handled every 800ms, and once after 100ms mouse is resting.

Demo 1, Demo 2

silencer.js

// Requires timer.js
function silencer( callback, delay, timeout ) {
	var delay_until = 0,
		timer = Timer(),
		now = Date.now || function(){ return +new Date(); };

	timeout = timeout || delay;
	
	function step() {
		delay_until = now() + delay;
		callback.apply( this, arguments );
	}
	
	return function() {
		if ( now() < delay_until ) {
			timer.set( timeout, step, this, arguments );
			
		} else {
			timer.clear();
			step.apply( this, arguments );
		}
	};
}

timer-normal.js

var Timer = (function( G ) {
	
	return function Timer( g ) {
		g = g || G;
		
		var noargs = [],
			timer_id,
			callback,
			context,
			args;
		
		function onTimeout() {
			var _callback = callback,
				_context = context,
				_args = args;
				
			timer_id = callback = context = args = 0;
			_callback.apply( _context, _args || noargs );
		}
		
		return {
			set: function( delay, _callback, _context, _args ) {
				callback = _callback;
				context = _context;
				args = _args;
				
				timer_id && g.clearTimeout( timer_id );
				timer_id = g.setTimeout( onTimeout, delay );
				
				return this;
			},
			
			clear: function() {
				if ( timer_id ) {
					g.clearTimeout( timer_id );
					timer_id = callback = context = args = 0;
				}
				return this;
			}
		};
	};

})( this );

timer.js

// Timer implementation that reduces setTimeout/clearTimeout calls.
// NOTE: something worse accuracy in not WebKit browsers (JS time accuracy).
var Timer = (function( G ) {
	
	return function Timer( g ) {
		g = g || G;
		
		var noargs = [],
			Date = g.Date,
			now = Date.now || function(){ return +new Date(); },
			timer_id,
			end_time,
			callback,
			context,
			args;
		
		function onTimeout() {
			var dt = end_time - now();
			
			if ( dt > 0 ) {
				timer_id = g.setTimeout( onTimeout, dt );
				
			} else {
				var _callback = callback,
					_context = context,
					_args = args;
					
				timer_id = callback = context = args = 0;
				_callback.apply( _context, _args || noargs );
			}
		}
		
		return {
			set: function( delay, _callback, _context, _args ) {
				var t = end_time;
				end_time = now() + delay;
				
				callback = _callback;
				context = _context;
				args = _args;
				
				if ( !timer_id || end_time < t ) {
					timer_id && g.clearTimeout( timer_id );
					timer_id = g.setTimeout( onTimeout, delay );
				}
				
				return this;
			},
			
			clear: function() {
				if ( timer_id ) {
					g.clearTimeout( timer_id );
					timer_id = callback = context = args = 0;
				}
				return this;
			}
		};
	};

})( this );