The server that has been hosting markworld.com for over a decade died early December 11. I am not sure that I have all the source code, but I'm looking for it. By far the most popular feature is the Rocket Altitude Predictor and, fortunately, this facility lives on another server so survived the outage. You can access it with this link:
The Electrical Circuit Simulator also survived.
You can see some of my photography HERE
Watch a an trailer for a non-existant movie of Wicked
More samples of my film work at Spark Digital Media