I took a look at the Mensa IQ test which is designed for people in the 98th percentile of other IQ tests. This test contains 60 multiple choice questions and is designated for a 40 minute time period. Most questions on this assessment were logical or sequencing questions where the user basically has to discover the pattern. I don't really see how this is a useful test of intelligence because many of the patterns seemed really simple and elementary. I can't believe that this would be complex enough for someone who is considered at the 98th percentile of intelligence (unless I am clearly just misreading each question!)
Once I finished the test, I realized also that you had to pay for the results, so not sure on the actual accuracy of this test.
Below is a sample test question: