  Well-quasi orders such as homeomorphic embedding are commonly used to ensure
termination of program analysis and program transformation, in particular
supercompilation.
  We compare eight well-quasi orders on how discriminative they are and their
computational complexity. The studied well-quasi orders comprise two very
simple examples, two examples from literature on supercompilation and four new
proposed by the author.
  We also discuss combining several well-quasi orders to get well-quasi orders
of higher discriminative power. This adds 19 more well-quasi orders to the
list.
