People are often surprised when I mention that awk is Turing complete. It's quite a powerful tool, I can't imagine loving the command line as much as I do without it.
It's really a low bar to clear. In fact, it would be far more surprising if a language such as awk with counters, conditional statements, the ability to jump to statements (i.e., loops), and the ability to change memory were not Turing complete.
Edit: clarity