Microsoft has created a Sandbox Microsoft Exam demo environment which is designed to help you become familiar with the exam interface and the different types of questions you'll come across in Microsoft Certification exams.
For people who are new to Microsoft Certification Exam and would like to get first hand Exam demo experience this is a great tool.
Access the Sandbox here: Microsoft Exam Sandbox
You can get more information on the various available certifications, Study guides, Self- Paced Training Modules etc. and also take the free Practice tests available for few of the Certifications from here: Microsoft Certifications