This chapter discusses non-conventional virtual reality mechanics, which utilize different body parts as part of the mechanics. The main motivation to research these topics is to increase the adoption rate of virtual reality for the general population as well as industry by finding mechanics with better usability in general and in specific scenarios. The main topics are comparing levels of realism in virtual reality mechanics, controller use compared to gestures, hand-tracking and the challenges and benefits of gesture-based interfaces, and eye-tracking. Additionally, interfaces that adapt to the user based on biological signals, such as heart rate, are explored. The topics are discussed through case studies presented in the chapter. The results showcase variations in usability between different interactions mechanics and overall find that non-conventional and namely natural interaction has a steep learning curve, and that it could be a viable option in certain use-case scenarios. Also, the previous related experience of the test users and the testing order of the mechanics influenced the results greatly. There are also implications about the impact of mechanics design on virtual reality sickness occurrence. The conclusion is that teaching and learning new ways of interaction is difficult, and due to general user familiarity with the pre-existing methods, it is challenging to judge the usability of the new design. The devices required can also be expensive, cumbersome, and inaccurate, which leaves room for improvement in the future.