i have discussion of collection of clock telling time digital interactive over here http://66.7.205.91/~lookangc/index.php?topic=333.msg752#msg752

some of the people here might be interested to look at them to get good ideas/features to modify the EJS open source version by Prof. Fu-Kwun Hwang

EJS could be a future platform for virtual labs/simulations for collaborations under creative commons licenses.