Recent observations of icy bodies in the asteroid belt point to the 
possibility of the existence of a new class of objects known as Main
Belt Comets (MBC).  These objects that are dynamically similar to the 
main belt asteroids (e.g., Tisserand numbers larger than 3), present 
physical characteristics  (e.g., dusty tails and comae) that resemble 
those of comets. The discovery of main belt comets has raised many 
questions regarding the origin, formation, and the activation 
mechanism of these objects. I present the results of an extensive 
numerical study of the dynamical evolution and collision probability 
of MBCs and discuss the implications of the results to the scenarios 
of the formation of these bodies. I will also discuss the probability 
of the collisions of these objects with smaller (i.e., m-sized) bodies 
as a possible mechanism for triggering their cometary activities