Quizify builds quizzes from information already on the web. It can make a quiz from a web page that includes a HTML definition list or acronyms and abbreviations. Otherwise, you can enter the information manually.
Quizify is designed to really help you learn the subject you're practicing. Quizzes are never-ending, you can practice as long as you want, and some quick stats let you know how well you're doing. Questions are not asked randomly, but based on how much you need to practice that question.