manufaktor · December 20, 2013 08:47 · Dec 20, 2013
diff --git a/number.js b/number.js
@@ -0,0 +1,16 @@
+  Number.prototype.toCurrency = function() {
+    var value;
+    if (isNaN(this) || !isFinite(this)) {
+      return '-';
+    }
+    value = Math.abs(this).toFixed(2);
+    value = value.replace(/(\d)(?=(\d\d\d)+(?!\d))/g, '$1,');
+    return (this < 0 ? '-$' : '$') + value;
+  };
+
+  Number.prototype.toPercent = function() {
+    if (isNaN(this) || !isFinite(this)) {
+      return '-';
+    }
+    return Math.abs(this * 100).toFixed(2) + '%';
+  };