That dude with magic blood that cured thousands of kids with a particular genetic defect. I don't remember his name (sadly), but I'm sure someone else here does.
EDIT: James Harrison. And it was 2.4 million babies.
Imagine donating blood as a way of paying forward the blood donations that kept you alive during your own surgery, and then finding out that you're some kinda superman with medicinal blood.
I'd say good old fashion politeness like saying good morning, giving someone a (real) compliment, and other small random acts of kindness. You do it because you want to not because you expect something.
Medics and nurses, when the patients aren't terminally ill (harm reduction). Whether they're "good people", and how often they do their jobs right can be debated, but properly caring for the sick is a good thing to do.
If we conceive of ethics as rooted in duty or virtue, rather than outcomes, we can then argue that simply doing your duty or being virtuous are good regardless of whether they lead to harm reduction or mitigation. The people here who have suggested just doing your job well (a duty) or being polite (a virtue) are putting forward a model of ethics based on these ideas.