This is a nice surprise.

My only knowledge with Environments came from Germán's work in the GSoC 
2010, as demonstrated here:

http://www.youtube.com/watch?v=n4I7fSVNX2A

Your work is quite different. No Environments added as classes in a 
browser. I remember importing code into an Environment being a 
showstopper. You've imported Seaside.

I guess you could have thirty Environments with thirty people doing the 
HelloWorld demo with #renderContentOn:. One image serving thirty people 
over the wire.

I imagine that the main concern is collisions and not security. But I 
guess if you're importing Smalltalk globals into Environment>>lookup, 
then you can mask out the classes you don't want an Environment to be 
able to access. Say, remove FileDirectory and FileStream, so that those 
hypothetical Seaside users couldn't explore the file system and send the 
results back to the browser.

Cool stuff.

Chris