Poor Man's Fiber (API compatible Thread based Fiber implementation for Ruby 1.8)
  (c) 2008 Aman Gupta (tmm1)

== Usage

f = Fiber.new{ |sym|
  p(sym)
  puts 'hi'
  p(Fiber.yield 1)
  puts 'bye'
  :end
}
p(f.resume :begin)
p(f.resume 2)

:begin
hi
1
2
bye
:end