In a medium sized bowl, whip the cream until soft peaks form. Melt the chocolate and fold into the cream. Spoon into 4 glasses.
Crush the oreos in the food processor or blender and spoon the crumbs onto the mousse.
Melt the white chocolate buttons and spoon into a small snaplock bag. Cut a small hole in the corner and pipe RIP onto the Tim Tams. Allow the chocolate to harden (this will only take a few minutes) and then stick the Tim Tam into the chocolate mousse.