Here are some links to some of my online multiple choice tests
I use Quia to make online multiple choice tests. Since my lab is kitted out with 12 tablet Pcs I can use these for testing in class. ( This saves me having to mark them and record the marks :-)) They are primarily for use by the students as a revision aid.
There are over 1000 questions, each time you open the test you get a random 15.
Now with FEEDBACK
If you get a question wrong you get feedback to tell you how to do it. As you can imagine this took a long time to set up but now its done I hope it proves useful.