iScholar™ is a content-neutral e-learning and corporate training authoring and publishing system that can be used to write on-line exams and course pages on virtually any topic and has support for interactive math. Requires: a JDK, Tomcat & MySQL
This features a text based, interactive auction manager programmed in Java. I think it is not full functional for a "real" use, but may serve as a basis to anyone who wishes to implement his/her own auction system.