Hi,

This link will be of interest to those wanting easy concurrency. Works 
best for simple cases and can be used as a primitive in building up more 
complex concurrency controls. However, use with caution, especially when 
larger amounts of code are being executed that could conflict with other 
threads is involved. This applies even in the single native thread 
multiple Smalltalk "light weight green" processes environment of most 
Smalltalks.

http://onsmalltalk.com/programming/smalltalk/smalltalk-concurrency-playing-with-futures/

Cheers,

Peter