" Speed Tracer is a tool to help you identify and fix performance problems in your web applications. It visualizes metrics that are taken from low level instrumentation points inside of the browser and analyzes them as your application runs. Speed Tracer is available as a Chrome extension and works on all platforms where extensions are currently supported (Windows and Linux). "
Backstretch is a simple jQuery plugin that allows you to add a dynamically-resized background image to any page. It will stretch any image to fit the page, and will automatically resize as the window size changes.