"D'oh! I _nearly_ asked the other day if Rails had a builtin method for this, decided not to, searched google and didn't see this.
My option is a lot shorter than to_sentence's code, but on the other hand, to_sentence *does* allow you to decide whether or not to skip the last comma, and to choose a connector other than "and" if you want. So much for DRY." - Phil Crissman