The following 10 year old Usenet article is quite interesting: http://groups.google.com/group/comp.lang.lisp/msg/4563e504dba92253
Although it is quite long and partly about Common Lisp, its main point is that enthousiasm and positive energy are the main/natural currency among developers. I think that this is also the main driving force behind Pharo. The author is Erik Naggum (http://en.wikipedia.org/wiki/Erik_Naggum), a programmer and (in)famous, provocative participant to many discussions. He died a couple of years ago. Sven
