Don't forget the changes in 1.9 http://railspikes.com/2008/9/8/lambda-in-ruby-1-9 http://railspikes.com/2008/9/8/lambda-in-ruby-1-9 And the much cooler Fibers,

Don't forget the changes in 1.9 http://railspikes.com/2008/9/8/lambda-in-ruby-1-9 http://railspikes.com/2008/9/8/lambda-in-ruby-1-9 And the much cooler Fibers, which you can think of as a reentrant block, kind of.