Hi, Ben and Saurabh.
SpriteMe was one of the most exciting tools I've created. I love the
style of dynamically modifying the actual code of the website while
the developer looks on.
Often the tools I build are "proof of concept", that I hope will
inspire development in other tools or be adopted by someone else as a
dedicated open source project. Example include UA Profiler (now
Browserscope.org), Episodes (now in Drupal, New Relic, and other
frameworks), and ControlJS (perhaps indirectly motivated work in other
JS loaders).
The code in SpriteMe motivated some of the spriting logic in Page
Speed, so the code has been useful. Unfortunately, the adoption of
SpriteMe has been far less, by an order of magintude, than what I
expected. Therefore, I'm no longer actively working on it. I encourage
you to fork the code and continue development if you find it useful.
-Steve