[Smalltakl is great>http://www.cincomsmalltalk.com/userblogs/knight/blogView?showComments=true&entry=3254944787] and alan gives us some of the reasons why. My addition to this list would have to be allinstances. This is both a bonus and a minus (as is most things). It's a security hazard because it lets you get all instances of a class.. but it's also a huge bonus because it lets you get all instances of a class! I bet someone could make a secure version that only gives you all instances of a class that you're allowed to know about...