The district I teach in has just implimented a new online testing software package, which although not nearly as powerful as Moodle, does have an a few advantages. I was asked to test some of the anti-cheating features and the auto-save feature yesterday before they put start the district benchmark testing. Here are a few of the things that I think would be a great addition to Moodle, as selectible options:
1) When the browser is minimized, the test (quiz) is locked and the teacher must allow the student back in.
2) The test auto saves answers as the students go along instead of having to press "Save without submitting" at the bottom.
3) If a student tries to open another program, and the browser looses window focus, the test is locked and must be unlocked by the teacher.
4)The teacher has the option to suspend a student during the test if they see the student doing something that warrants it.
I can see almost every computer screen in my room from just about anywhere, but when my back is turned.... I think these would be great features to add. My district's software is also browser based, so I am sure it is possible to add this to Moodle as well.