Biology

A possible long term goal here is to improve human life by creating a monkey with some human organs for drug testing. This field also has the prospect of growing human organs in pigs for transplants.

To be clear, being chimeric is not inheritable because the DNA is not being mixed. The animal has some cells from one species, and other cells from a different species.

Though you can argue about the ethics of this kind of animal research, I think biomedical research in general is valuable. To improve human welfare, I think it's important for humanity to have both low risk short term strategies (providing people with food and water), and long term high risk strategies (basic biological research).