New: You can see an example of an experiment here.
This software allows self-paced reading and speeded acceptability judgment tasks to be run online through a web browser. The server is written in Python and stores results in a CSV file, suitable for later analysis using R, Matlab, etc.
Version 0.2 has now been released. The code has been rewritten to make it more modular, allowing a greater variety of tasks to be run (and for easier addition of new kinds of task). There is some reasonably comprehensive documentation at Documentation.