RequestReduce is a free and open source ASP.NET resource that can quickly improve the speed of the websites.

It offers automated image-spriting, minification of JS-CSS and optimizes caching headers.

There is almost no details to configure for standard usage, it is more a plug 'n' play solution and works with any IIS-powered website (ASP.NET, ASP, PHP, etc.).

RequestReduce works with files that are hosted anywhere (locally or remotely) and can also compile Less, Sass or CoffeeScript.

CSS sprites are great for minimizing the number of requests our websites perform by collecting multiple images in a single one and displaying the appropriate ones using background-position.

However, once the images are placed on a canvas, finding the positions of each item is a time-consuming process.

SpritePad is an impressive web application (which is free) that simplifies the whole process by allowing us to drag 'n' drop any number of images to a canvas, position them how we want and get the auto-generated CSS rules.

The canvas size can be customized and/or can be shrinked to fit the document with a click.

Once we arranged all the items, SpritePad provides us a .zip file which consists of the sprite image + CSS rules.

P.S. There is also a "premium" plan which makes sharing the sprites with colleagues possible and has more features.

Spritely is a jQuery plugin for creating dynamic character & background animations using HTML + JavaScript.

With the power of JavaScript, the animations can be controlled on events (clicks, mouseovers) easily.

Animated elements can fly over the page without effecting any other element (can be ideal for floating-type banners) & the page still remains accessible.

Specially, for the platforms where Flash is not supported, Spritely can be an alternative (like iPhone, iPad).

It works in all major browsers including IE6.