I've run Squeak on an Cassiopiea A20E (80MHz Hitachi SH3 with keyboard).  It 
runs a bit slowly but is usable.  But it also regularly crashes the machine 
- but then so do many other programs.

My advice is if you want a PDA to use as a PDA stick with Palm(Pilot) - it's 
still the best.

Even if you got Squeak to run on a Windows CE Palm-sized PC would it be 
usable without a keyboard?

I've seen pictures of a colour Windows CE palmtop from HP but I don't know 
if you can buy it yet.  I think it uses a 100MHz SH3 - I hate to think what 
the battery life is like.

Julian