diff --git a/mock-interactions.js b/mock-interactions.js
index 0c32c7b..c41f76f 100644
--- a/mock-interactions.js
+++ b/mock-interactions.js
@@ -1,27 +1,104 @@
+/**
+ * @license
+ * Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
+ * This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
+ * The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
+ * The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
+ * Code distributed by Google as part of the polymer project is also
+ * subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
+ */
+
 (function(global) {
   'use strict';
 
-  function focus (target) {
-    Polymer.Base.fire.call(target, 'focus');
+  var HAS_NEW_MOUSE = (function() {
+    var has = false;
+    try {
+      has = Boolean(new MouseEvent('x'));
+    } catch (_) {}
+    return has;
+  })();
+
+  function middleOfNode(node) {
+    var bcr = node.getBoundingClientRect();
+    return {
+      y: bcr.top + (bcr.height / 2),
+      x: bcr.left + (bcr.width / 2)
+    };
   }
 
-  function blur (target) {
-    Polymer.Base.fire.call(target, 'blur');
+  function topLeftOfNode(node) {
+    var bcr = node.getBoundingClientRect();
+    return {
+      y: bcr.top,
+      x: bcr.left
+    };
+  }
+
+  function makeEvent(type, xy, node) {
+    var props = {
+      bubbles: true,
+      cancelable: true,
+      clientX: xy.x,
+      clientY: xy.y
+    };
+    var e;
+    var mousetype = type === 'tap' ? 'click' : 'mouse' + type;
+    if (HAS_NEW_MOUSE) {
+      e = new MouseEvent(mousetype, props);
+    } else {
+      e = document.createEvent('MouseEvent');
+      e.initMouseEvent(mousetype, props.bubbles, props.cancelable, null, null, 0, 0,
+        props.clientX, props.clientY, false, false, false, false, 0, null);
+    }
+    node.dispatchEvent(e);
   }
 
-  function down (target) {
-    Polymer.Base.fire.call(target, 'mousedown');
+  function down(node, xy) {
+    xy = xy || middleOfNode(node);
+    makeEvent('down', xy, node);
   }
 
-  function up (target) {
-    Polymer.Base.fire.call(target, 'mouseup');
+  function move(node, fromXY, toXY, steps) {
+    steps = steps || 5;
+    var dx = Math.round((fromXY.x - toXY.x) / steps);
+    var dy = Math.round((fromXY.y - toXY.y) / steps);
+    var xy = {
+      x: fromXY.x,
+      y: fromXY.y
+    };
+    for (var i = steps; i > 0; i--) {
+      makeEvent('move', xy, node);
+      xy.x += dx;
+      xy.y += dy;
+    }
+    makeEvent('move', {
+      x: toXY.x,
+      y: toXY.y
+    }, node);
   }
 
-  function tap(target) {
-    Polymer.Base.fire.call(target, 'tap');
+  function up(node, xy) {
+    xy = xy || middleOfNode(node);
+    makeEvent('up', xy, node);
   }
 
-  function downAndUp (target, callback) {
+  function tap(node) {
+    var xy = middleOfNode(node);
+    down(node, xy);
+    up(node, xy);
+    makeEvent('tap', xy, node);
+  }
+
+  function focus(target) {
+    Polymer.Base.fire.call(target, 'focus');
+  }
+
+  function blur(target) {
+    Polymer.Base.fire.call(target, 'blur');
+  }
+
+  function downAndUp(target, callback) {
     down(target);
     Polymer.Base.async(function() {
       up(target);
@@ -31,7 +108,21 @@
     });
   }
 
-  function keyboardEventFor (type, keyCode) {
+  function track(target, dx, dy, steps) {
+    dx = dx | 0;
+    dy = dy | 0;
+    steps = steps || 5;
+    down(target);
+    var xy = middleOfNode(target);
+    var xy2 = {
+      x: xy.x + dx,
+      y: xy.y + dy
+    };
+    move(target, xy, xy2);
+    up(target, xy2);
+  }
+
+  function keyboardEventFor(type, keyCode) {
     var event = new CustomEvent(type);
 
     event.keyCode = keyCode;
@@ -40,30 +131,30 @@
     return event;
   }
 
-  function keyEventOn (target, type, keyCode) {
+  function keyEventOn(target, type, keyCode) {
     target.dispatchEvent(keyboardEventFor(type, keyCode));
   }
 
-  function keyDownOn (target, keyCode) {
+  function keyDownOn(target, keyCode) {
     keyEventOn(target, 'keydown', keyCode);
   }
 
-  function keyUpOn (target, keyCode) {
+  function keyUpOn(target, keyCode) {
     keyEventOn(target, 'keyup', keyCode);
   }
 
-  function pressAndReleaseKeyOn (target, keyCode) {
+  function pressAndReleaseKeyOn(target, keyCode) {
     keyDownOn(target, keyCode);
-    Polymer.Base.async(function () {
+    Polymer.Base.async(function() {
       keyUpOn(target, keyCode);
     }, 1);
   }
 
-  function pressEnter (target) {
+  function pressEnter(target) {
     pressAndReleaseKeyOn(target, 13);
   }
 
-  function pressSpace (target) {
+  function pressSpace(target) {
     pressAndReleaseKeyOn(target, 32);
   }
 
@@ -73,6 +164,8 @@
     down: down,
     up: up,
     downAndUp: downAndUp,
+    tap: tap,
+    track: track,
     pressAndReleaseKeyOn: pressAndReleaseKeyOn,
     pressEnter: pressEnter,
     pressSpace: pressSpace