As long as people are mentioning PST, just so others know, there is a 
project alive whose goal is to build an embedded IO based (i.e. 
intrinsically headless) Smalltalk (called Wisp). It is derived from the 
PST VM. It's far from really stabilized, having had most of the work 
done on it at CS4. We have test run it on a variety of Unix based 
platforms (yes 3 + 4 was the first test), including uClinux on a couple 
M5272 Coldfire boards.

8K is, well, small. I'm just not seeing it happen with Smalltalk, even 
Wisp. The 'size' of the Wisp VM (built for x86linux) is 27026 bytes. 
There's probably still some Palm related stuff we haven't hunted down 
and removed which will make it smaller, but we also plan to add 
primitives for socket support and that will undoubtedly offset that. An 
unstripped version of the image is about 10K. I imagine with some dead 
code removal, we could shrink that some, but still, 8K is just very very 
small for a GC'ing system with lots of indirection in it. The Wisp wiki 
page is at <http://wiki.cs.uiuc.edu/CampSmalltalk/Embedded+Smalltalk>. 
Martin McClure has also set up a mailing list.

In some ways Wisp/PST are very classical Smalltalk, but in others they 
are not.

-- 
Travis Griggs
Key Technology
10 2 letter words: "If it is to be it is up to me"

At one point during CS4, Michael (forget last name) actually built and 
executed a 178 byte image.