For what it's worth, I've had Squeak 2.7 hang on me a couple of times,
and I once had to reboot a Mac running Squeak 3.0.  But then who knows
_which_ program was responsible for that?  For the record, the two
most crash-prone programs on the Macs here seem to be Microsoft Word
and Netscape, possibly because they are the most used programs on our Macs.
Squeak is a *dream* of stability in comparison.

It must be acknowledged that a programming language where you can do
	Smalltalk keys do: [:k| Smalltalk at: k put: nil]
(which reliably kills Squeak 3.0) is one that is going to be subject to
crashes of a kind not common in other programming languages.

Interlisp-D/Xerox Common Lisp got around that by keeping a set of global
variables that you were allowed to smash and another set that you weren't.
(If you _really_ knew what you were doing, you could move a variable from
one set to the other, make your change, and then move the variable back to
the dont-change-me set.  If you _thought_ you knew what you were doing, it
was reboot time.)

When the programming language Pop was invented, it also served as the
time-sharing operating system for the (by today's standards miniscule)
machine it ran on.  Early Pop programmers had a game:  how much of the
system can you delete while still leaving enough for a graceful shutdown?